THEHISTORY OF MUSIC LIBRARY |
THE HISTORY OF MUSIC (art and Science)FROM THE EARLIEST RECORDS TO THE FALL OF THE ROMAN EMPIRE.
CHAPTER IX.
Basis of the science. Its fundamental laws. Earliest
uses of music. Mathematical divisions of strings not alone sufficient. Minor tones introduced by Didymus, and followed by
Claudius Ptolemy. Neither the Greek scale nor the modern is properly in one
key. Hence the question whether
Elevenths were concords. How to test intervals. The true proportions for scales. Rules for adding and deducting intervals. Scales of Didymus and of Ptolemy. Defects of the
modern scale. The law of Nature the only true guide. Objections to the Fourth and minor Seventh of the
present scale. Causes of Concord and
Discord. Pythagorean ideas realized by modern science. Sounds too high and too low for our hearing.
THE discussion, of ancient and modem science
must, in a measure, go hand in hand; for, as our present scale is Greek, so
whatever applies to ancient times is equally applicable to the present. No
science has more fixed and clearly established fundamental laws than music. The
wind will teach them as it plays upon the strings of an Aeolian harp; for,
although tuned to one pitch, it will cause them to emit sounds of every
variety. The same law exists in the natural sounds of a trumpet, horn, or open
tube of any kind, and all the notes will follow in the same succession. By
blowing into the tube so slowly as just to make the sound continuous, the
lowest, or fundamental note, produced by the entire length of the pipe is first
heard; then, by gradually increasing the rapidity of the breath, an ascending
series of notes will follow; every one of which may be predicted as they
rise gradually, higher and higher, up to the extreme pitch that can be obtained
from the breath of the mouth. The same rising succession of notes is heard in
the harmonic sounds that follow upon one of the long strings of a pianoforte,
after the fundamental note, produced by the whole length of string, has been
struck, and when the string gradually subdivides itself into smaller and
smaller nodes before finally coming to rest. They then follow so rapidly as to
seem to run one into the other. From these laws, we may deduce both a perfect
Diatonic, and a perfect Chromatic scale from any given note. The proportions of
musical intervals may be measured either by the divisions of a string, or by
the gradual cutting down of a pipe. Results in harmony may be foretold with
certainty as either good or bad, by calculating the proportions of the
intervals together with the roots of the sounds, and without any appeal to the
ear. Again, the ears may be stopped, and the eye will tell, from the motions of
sand scattered upon the sounding board of a pianoforte, or any other vibrating
surface, whether the chord that has been struck upon the instrument has been a
concord or a discord. In the former case, the movements of the sand will be
symmetrical and regular; and, in the latter, they will show that discord reigns
by their disturbed state, and by their seeming to battle together. The Octave
is the first ascending sound, after the primary one, in the harmonic scale of
nature, and all subsequent sounds are but subdivisions of it at higher pitches.
The Octave system, with its included and harmonic-following Fifth and
Fourth, and major and minor Thirds, is the foundation of all music. Sound, as
is well known, does not exist in the atmosphere, but is an affection of the
brain produced by succeeding elastic waves of air that strike upon the drum of
the ear, and which, for that reason only, are called “sound-waves”.
From all this, and from much more that might be said,
there can be no more evident fact than that it was the design of the Creator
that music should be the companion and the solace of man; and from this we may
deduce that, in the mouth of man, there can be no more fitting medium for the
praise of his Maker.
The ancient heathen attributed a divine origin to
their music, and, accordingly, the earliest uses to which we find it to have
been applied by them are those of religious worship. At a later period, music
was also cultivated for educational purposes, especially among the Greeks, and
chiefly with the view of elevating the mind above its too frequently grovelling tendencies. “The first and noblest application
of music”, says Plutarch, “is in offering the tribute of praise to the
immortals: the next is the purifying, regulating, and harmonizing the soul.”
Speaking of times past, Plato says: “Our
music was then divided according to certain species and figures. Prayers
to the gods were one kind of song, to which they gave the name of hymns.
Opposed to this was another species which might be called Threni (Funeral Dirges), another, Paeans (Choral Songs to Apollo or Artemis), and another, The Birth of Dionysus (the
Greek Bacchus), which I hold to be the dithyrambic verse. There were also Nomes (or simple and severe chants upon a few high
notes), accompanied by the Kithara, which were equally distinct. These and some
others being prescribed, it was not allowable to use one kind of chant for
another. But, in process of time, the poets introduced unlearned license; they,
being poetic by nature but unskilled in the rules of the science, trampled down
its laws. Over-attentive to please, they mixed threni with the hymns, and paeans with dithyrambs, imitated music intended for
the flute upon the Kithara, and confounded each kind with every other.” (Laws,
lib. 3.) Add to this Plutarch’s account. He says: “In the yet more early times,
the music of the theatre was unknown to the Greeks; the whole art being then
made subservient to the honour of the gods, and to
purposes of education. Theatres themselves were then unknown; and their only
music consisted of those sacred strains which were employed in the temples as a
means of paying adoration to the Supreme Being, and of celebrating the praises
of the great and good of our species. It is probable that the modem word ‘Theatre’
and the very ancient one theorein (to look
at), have their derivation from Theos, the Deity. In the present day, so
great is our degeneracy, that we have absolutely lost both the knowledge
and the notion of that system by which youth were formerly trained up to honour and virtue. The only music now studied and listened
to is that of the theatre.” (De Musica, cap. 27.)
Notwithstanding the divine origin attributed to music,
it is very doubtful whether any of the civilized nations of antiquity knew the
laws of Nature as to the prescribed succession of musical sounds, or, perhaps,
much beyond the general observation, such as that of Aristotle, that high notes
are of more rapid vibration than low ones. So far as we are acquainted with
ancient systems of music, they seem to have been founded upon the divisions of
a string upon some instrument of the monochord kind, with a movable bridge (hupagogeus) under it, for the purpose of measuring;
or else to divide by pressing the string against a finger-board Since, then,
the science of music was thus learnt from a string, it must surely offer the
most simple and intelligible means of explaining it. It will give the least
amount of trouble to the reader; and, although there must be figures in all
cases, yet, if explained by a string, nothing more than the elementary rules of
arithmetic can be required.
The Greek system is defective in one essential point, that, although the divisions of a string will show the
ratios that its parts or intervals bear to the whole length, they will not
point out the positions in which those intervals must be placed in a musical
scale, so as to make consonances of them by keeping them within one key,
or from one root. So, a scale may look well-proportioned upon paper and yet be
practically bad. The same length of a string may be divided off in one part, so
as to be concordant with the rest; and, in another part, to be discordant.
The defects of this origin are shown in many of the
Greek scales, and, among others, in our own, it being wholly Greek.
The Octave, the Fifth, the Fourth, and the major tone,
(i.e., sounding eight-ninths of a string compared to the whole length,)
were included in the Pythagorean system of music; and the seemingly slight
change which created true consonant major and minor Thirds, and the minor tone,
(of nine-tenths of a string compared to the whole,) were improvements
introduced by Didymus about the commencement of the Christian era, and followed
by Claudius Ptolemy, about the year 130 or 140. Still, the Greek Diatonic scale
remained a compound of sounds derived from different roots, and was, and is,
therefore, strictly speaking, in different keys.
For instance, in our adopted scale of C major,
one-half of the Diatonic Octave, or the notes on the long keys of the
pianoforte, is in the scale of C, and the other half is derived from the scale
of F. This is consequent upon its having been composed out of two Greek
conjoined tetrachords, B, C, D, E, and E, F, G, A, which, when taken as parts
of a major scale, and not of a minor, as of old, have their roots or key-notes
the one in C and the other in F. If a minor scale were to be tested in the same
way, it would show greater variety of roots, therefore greater deviation from
the right path.
A comparison with the scale of Nature will presently
prove this; but, in the meantime, in order that the purport of these remarks
may be understood, suppose that, in the key of C major, we sound C in the base,
and with it C and F in the treble, the last two being at the interval of a
Fourth. The treble F makes a discord with the base C. But if we again sound the
upper C with the G immediately below it, instead of the F above, and retain C
as the base, it is a concord. And yet from G to C, and from C to F, are both
Fourths taken from the key-note, the one above and the other below it, in our
key of C. The difference is, that from C to F is an artificial interval,
disavowed by Nature in her scale of C, but from G to C is Nature’s interval.
The former is from the root of F, and requires F for its base. Then
it will be concordant. These cases will be further exemplified in the sequel.
As my present subject is the Science of Music, I speak
freely of the defects of our adopted scale. Its deficiencies may at least be
made known, however improbable any change of system may be. Let us face the
difficulties, and see what a dwarfed scale for melody we have to work upon,
through having copied from the Greeks.
The intervals from G to C and from C to F, were two of
the puzzles to writers upon Harmony, not only for several ages past, but even
far into the present century. They had no rule by which they could duly account
for Fourths being both discords and concords in what was considered to be one
key, so they divided themselves into opposite camps; the one contending that
Fourths, and what have been called ‘Elevenths’, or combined Octaves and
Fourths, were concords, and the other as stoutly maintaining that they were
discords. Neither of the two parties thought of appealing to the Harmonic scale
for the solution of the difficulty. Harmonics were, until lately, more looked
upon as a trouble to pianoforte makers that ought to be got rid of, than as
containing the essence of music, and as being therefore a necessary study for a
musician. There is indeed little that can be more instructive than a comparison
of our scale, calculated by Greek mathematicians, with that most ancient of all
scales, the scale of Nature. Every
musical interval within the Octave may be so misplaced as to leave the key and
become a discord, and it is from the scale of Nature only that a fitting
position for each has to be determined. Mathematical scales are insufficient
without it, and yet this material deficiency in them, and especially in our own
scale, has been but little thought of. A choice of good intervals may suffice
for varied harmony, but to be consonant in one key, they must be derived
from the same root.
The Greek scale which preceded the time of Didymus,
although usually coupled with the name of Pythagoras, might equally be called
the scale of ancient Asia, and of ancient Egypt. It has already been shown that
the Greek one-octave scale began a Fourth below the key-note, thus taking the
interval of the Fourth downward in its consonant form to the key-note or Mese,
and that it ended a Fifth above the key-note. Also that the Fifth above the
key-note was compounded of a major tone, called diazeuctic,
or disjunctive, and of another Fourth. So the skeleton of the Octave was
thus complete, and there remained but to fill up the two Fourths by smaller
intervals. So far the Greek scale and the scale of Nature agree, and from that
point they part company. These Fourths were originally subdivided, each into
two major tones and a remnant. The choice of major tones was directed by one of
them being the exact interval between a Fourth and a Fifth. When two of them
were included in a Fourth, the remnant became one of that kind of semitone
which was in the ratio of 243 to 256, to which the name of a diesis was
given by the earliest Pythagoreans, such as Philolaos,
but which later Pythagoreans named limmas,
meaning remnants of the interval of the Fourth, after the two tones were
taken out of it. Aristoxenians and Greek practical
musicians called these remnants semitones, but such semitones are different
from the semitone of later Greek, and of modern music.
When the Greek scale was extended to two Octaves, by
adding on a Fifth at the lower extreme of the original Octave scale, and a
Fourth at its upper end, the two-octave scale began and finished at the
key-note, like our own, and equally agreed with Nature’s law as to the skeleton of
the Octave. Therefore, for the comparison of ancient with modern music, which
is here proposed, we will take one Octave in this latter form. Suppose the key
to be Hypo-Dorian, or A minor, then from A to B will be the disjunctive tone,
and there will remain the two conjoined Fourths, B, C, D, E, and E, F, G, A,
just as on the long keys of a pianoforte.
The way to test such intervals as the Octave, the
Fifth, the Fourth, the major Third, and the minor Third, upon a string, is
to stop successively the half, the third part, the fourth, fifth, and sixth
parts, and to sound the remainders of the string, comparing each of these
intervals with the sound of the whole length. We have no equivalent in modem
music to the note produced by stopping the seventh part of a string, which is
the Harmonic Seventh, but it is a natural note upon the horn. It was employed
in the last century with untempered instruments, such
as fiddles and basses, in small bands, as well as for ages before, when horns
and trumpets had no keys or slides. It affords additional passages in melody
without change of key. It is called the Harmonic Seventh in reference to its
key-note, so, in C, would be called Harmonic B flat, and we might employ it
where we cannot use our B flat, because the latter does effect a change of key.
Swiss singers, says Spohr, in his Autobiography, employ the Harmonic Seventh in
their music, as well as the Harmonic Fourth, which is the interval produced by
stopping the eleventh part of a string. They are quite right to do so, because
they enlarge their sphere of melody, and have Nature on their side in both
cases. The Harmonic B flat divides the upper Fourth, from G to C in the key of
C, into two all-but-equal parts, and these might be called Thirds, but they are
of diminishing compass, and next to the minor Thirds that we employ. Natures
Octave is divided into eight tones, beginning with the eighth part of a
string up to the sixteenth part; but we, following the Greeks, Chaldeans, and
Egyptians, with their seven planets and seven notes, have still but seven.
Nature divides the interval, from G to C into the same number of parts as that
from C to G.
As the seventh part of a string gives the Harmonic B
flat, so the eighth part stopped gives the key-note, C, above it. I have
already said that the stoppings of the ninth and of the tenth parts of a string
raise its pitch by the intervals of our major and of our minor tone. From
those, the moderns pass on to the sixteenth part, and by stopping it, they
raise the note by what is now termed indifferently a major semitone, or a
Diatonic semitone. When we pass down from C to B, or from F to E, it is by the semitone
in question. Its name is from the Latin, and that of hemitone from the Greek, but they are equally improper; because, instead of being a
semitone, the interval of a sixteenth part of a string is really the smallest
of the eight tones of Nature. It is too wide to be the half of even our major
tone. Its name should have been changed when Didymus and Ptolemy enlarged its
proportions. The Pythagorean limma, or Aristoxenian semitone, was as 243 to 256, and Didymus
changed it to 240 to 256, which is as 15 to 16.
A true tonal scale is from the eighth to the sixteenth
part of a string, whatever the length of that string may be. Length only
changes the fundamental note. The two intervals to which we give the name of
tone are the largest of the eight of Nature’s. Those eight decrease
progressively in the ascending Octave; and we employ but three of them, viz.,
the largest two, and the least. We name the first two Tones, and this
least we misname a major or Diatonic semitone.
There is another, and a truer semitone, in modem
music. It is produced by stopping the twenty-fifth part of a string, and
therefore is much less than the Diatonic semitone. It is the true interval
between G and G sharp in Nature’s scale, when C is the fundamental sound, or
key-note. This semitone, like the other, has two names. It is called minor,
and Chromatic, and it is employed when the name of the note remains
unchanged, as from F to F sharp, or from G to G sharp.
All the before-named intervals were used by the Greeks
in some one or other of their scales. Even the Harmonic Fourth and the Harmonic
Seventh were thus included.
Our major and minor semitones were coupled together in
the Chromatic scale of Didymus, and the two combined are equal to one minor
tone. Hence, when he added the usual interval of a minor Third between the
highest two strings of the Fourth or tetrachord, he made the best possible
arrangement for a Greek Chromatic scale. With two such tetrachords, and the diazeuctic major tone, he completed the Octave.
His Enharmonic scale was equally good, for he divided
his major semitone, 15/16, into its two best quarter-tones, 30/31, and 31/32.
Then a major Third, 4/5, completed that tetrachord.
But, before referring further to figures, there are
three simple rules that every incipient musician should know. It is not,
however, to be assumed that all do know them; for although it must be
supposed that there are books on music which contain these rules, yet it has
not been my fortune to have met with any one of them. Musicians appear too
generally to have thrown such information aside, and mathematicians, when
writing upon music, assume that their readers know every kind of rule
beforehand.
It is indispensable for a real musician, that he shall
be able to tell with certainty what will be the effect of any combination of
intervals, and he may often wish to ascertain it for himself when he cannot
have the opportunity of testing them practically. It is well, therefore, to
know how he can judge of them on paper, with even greater certainty than by
ear, however good that ear may be. Indeed, it is by far the more convenient way
of testing unfamiliar intervals.
The three rules are: How to add intervals; How to
deduct one from another; and How to compare one with another. The answer to all
may be comprehended in a line. To add, multiply; To deduct, cross-multiply; To
compare, bring them to a common denominator. Still, these directions will not
be, in all cases, sufficient; and, in order to be understood by all, I hope to
be excused for further explaining and exemplifying them.
To add one interval to another, multiply the numerator by the numerator, and the denominator by the denominator. If we
say three-eighths, three is the numerator, and we denominate eighths. Then
reduce the multiplied totals to their smallest figures, by finding out what is
their “Greatest Common Measure”
To do this, we must follow the ordinary rule of
arithmetic, which is thus expressed: “Divide the greater by the less, and the
preceding divisor by the remainder, and so on continually until there is no
remainder. The last divisor will be the Greatest Common Measure.”
This will perhaps be more quickly understood by an
example. The ancient Pythagorean tetrachord, or Fourth, consisted of two major
tones and a limma, or remnant; in other
words, of the three intervals, 8/9, 8/9, and 243/256.
Then for the two major tones and limma = 8/9 x 8/9 x 15552/20736 to be explained
thus :
For the numerator, 8 times 8 are 64, and 64 times 243
are 15552. For the denominator, 9 times 9 are 81, and 81 times 256 are 20736.
Divide the greater by the less, 20736 by 15552; it leaves 5184. Then 15552 by
5184, and it leaves no remainder. Therefore, 5184 is the last divisor, and the
Greatest Common Measure. Divide the two original sums by 5184; it shows
15552/20736 to be equal to 3/4.
For the second rule: To subtract one interval from
another, by cross-multiplication, the readiest way is to invert the figures of
one of the two ratios, and to place them under the others. Then to multiply the
upper by the under. This position of the figures is the more convenient for a
sum. To prove the rule in the simplest way, we know that 4 to 2 is the same
ratio as 2 to 1. Cross-multiply, and it will show them to be equal. Again,
we know that a Fifth and a Fourth together make an Octave, as from C up to
G, and from G to Octave c. Therefore, if we deduct a Fifth from an
Octave, the remainder ought to be a Fourth. The ratio of the Octave is as 1 to
2 in length, or as 2 to 1 in vibrations. The interval is the same either way,
so the case may be stated either way. Here, adopting the former, the Fifth is
as 2 to 3, and the Fourth as 3 to 4.
Therefore, taking the Octave
as ......................1:2
Multiply by the inverted figures of the Fifth……...3 :
2
The remainder shows the Fourth, viz……............... 3:4
For the third rule: How to compare intervals. The most
useful example will be to take our present scale, and to compare every interval
with its keynote in C. To D is a major tone, 9/8, or as 9 vibrations to 8 of
the key-note. To E, a major Third, or 5 vibrations to 4 of the key-note. To F a
Fourth, in figures 4/3. To G a Fifth, 3/2. To A a Sixth, in figures 5/3. To B a major Seventh, 15/8.
Lastly, the Octave is as 2 to 1 of the key-note. So the scale stands thus : 1,
9/8, 5/4, 3/2,5/3, 15/8, 16/8. As the
C, D, E, F, G, A, B, C.
Octave here includes odd numbers, as four to three,
and five to three, which are two of the imperfections of our scale, we cannot
have a lower common denominator than 24, where it ought to be 8. So we must
multiply every ratio by such figures as will bring its under-figures to 24. For
instance, 9/8 is equal to 27/24, multiplying by 3. Next, we must multiply 5/4
by 6, and so on: 24, 27/24, 30/24, 32/24, 36/24, 40/24, 45/24, 48/24.Then
dropping the lower figures, we compare the proportions of our Octave scale as
24,27, 30, 32, 36, 40, 45, 48.
This rule, or multiplying the ratios by 24, is
necessary for understanding Dr. Wallis’s edition of Claudius Ptolemy, and many
more books.
When the principal intervals are stated in figures,
according to their proportionate vibrations, the Octave is written 2/1,
or 2 to 1. The Fifth as 3/2, or 3 to 2. The Fourth as 4/3. The major Third as
5/4, and the minor Third as 6/5. The major, or Diatonic semitone, as 16/15.
And now, having given the three necessary rules, I
will in future state only the results, and leave them to be tested by the
curious.
One of the Greek scales in which the Harmonic Seventh,
or seventh part of a string, was employed, is exceedingly worthy of note, and
quite an exceptional scale in Greek music. It is the Even Diatonic (Diatonon homalon)
of Claudius Ptolemy, given in the 16th chapter of his first book. The
remarkable part is, that he follows out the natural division of the scale in
all the intervals that are included in the Fifth, from the key-note upwards.
Therefore he has so far a true major scale, with its major Third,
instead of the perpetually recurring minor Third that minor Third being always
consequent upon the disjunctive major tone immediately above the keynote, and
to the semitone of the tetrachord being next above it, as A to B, and B to C.
They caused Greek scales to be always minor. Jean Jacques Rousseau’s remark,
that the minor scale is not given by Nature, is a very just one. After the
major Third, which is in the place of the old minor, Ptolemy employs the
Harmonic Fourth, or the eleventh part of a string, being a nearly equal
division between E and G. So, in the scale of C, Ptolemy has C,
D, E, Harmonic F (instead of our F), and G. Next, as to the
tetrachord, or Fourth, below the key-note, he first divided it into its two
legitimate parts by Harmonic B flat. So far he had proceeded thoroughly
according to natural laws, but as that one division of the Fourth gave him only
three notes: G, Harmonic B flat, and C;
and four were required for a Greek tetrachord, he altered that excellent
arrangement, and repeated the intervals that he had just employed in the Fourth
above the keynote, viz., for the D, E, Harmonic F, and G.
Before that change, he had adopted Nature’s scale so
far as taking successively the sixth, seventh, eighth, ninth, tenth, eleventh,
and twelfth parts of a string. Yet he was not led to it by any insight into
Nature’s laws, but by one of the Pythagorean doctrines which neither Pythagoras
nor his school had ever carried out. The doctrine was to employ only
super-particular ratios, such as 10 to 9, 9 to 8, 8 to 7,7 to 6, 6 to
5, 5 to 4, 4 to 3, and 3 to 2. As Ptolemy here employed them in gradually
decreasing intervals, he fell into the law of Nature.
When the Pythagoreans gave the name of limma to the proportions of 243 to 256, which
are less than the half of a major tone, they called the remaining greater part
an apotome, or segment. It had the awkward proportions of 2048 to 2187.
The comparative sizes of the two will be made clearer if we multiply the
figures of the limma by 8, thus
making it 1944 to 2048. The difference between these two was called a
Pythagorean comma (komma), viz., 524,288 to
531,441. Therefore, if a Pythagorean comma be added to two limmas, it makes one major tone. But there is
another point to be noticed about this comma. If twelve perfect Fifths be taken
from any note, say from C upwards, they will end upon B sharp, and it will be a
Pythagorean comma sharper than the seven-octave C. The reason of this reversal
of order is, that we make Fifths where Nature has not designed them, because
the notes have to serve other purposes. Octaves are the only continuously
perfect intervals.
A few other intervals with peculiar names will
sometimes be met with; and, being bound to explain them, it is better at once
to clear the board. A minor semitone deducted from a major semitone, leaves
what is now termed an Enharmonic diesis, 125 to 128.
This diesis is less than one of the Enharmonic-quarter tones
of Didymus,31/32 = 124/128. The modern Enharmonic diesis is a
nominal difference between C# 3 and Db. The interval between our Diatonic,
or major semitone, and a major tone is 128/135.
A Greek Enharmonic diesis, or
quarter-tone, is sometimes called a Tetartemorion, meaning quarter-piece
of a tone, and a Chromatic diesis, or third part of a tone, is
called a Tritemorion. These two intervals have not infrequently
been mistaken by lexicographers for the much larger ones of a Fourth, which is
two tones and a half, and of a Third, which is two tones.
A Schisma is an interval to be read
of in mathematical music, but one not often brought into practice. It is the
approximate half of a Pythagorean comma. A Diachisma is
a similar division of the before named limma. As
the interval of a Diachisma approaches
to a quarter-tone, it may have been practically employed in the ancient
Enharmonic scale.
Lastly, the comma of Didymus is sometimes referred to
as a syntonic comma. This is an important interval in modern as well as in
ancient music. It is far more so than the comma of Pythagoras. The comma of
Didymus is the interval between a major and a minor tone, or between the
eightieth and the eighty-first parts of a string.
So delicately organised is
the human ear, that it was but this eighty-first part that worked the great
revolution between the ancient scale of Pythagoras and the very present scale.
First, Didymus, and, after him, Claudius Ptolemy, deducted this comma from one
of the two major tones that formed the ancient Ditone,
or over-sized major Third, and so changed it into our consonant major Third.
Moreover, the comma thus taken away from the tone was added to the limma, and brought that interval into its present
proportions as a major semitone. By these changes the Greek Diatonic scale
attained its present improved proportions. So, the difference between a major
and a minor tone, as well as that between a limma and a major semitone, is a syntonic comma, or comma of Didymus, or the
eighty-first part of a string.
To prove the effect of this apparently small, but
really very important, change, we have but to add together the two major tones
of which the ancient Ditone, or Pythagorean
Third, consisted, by multiplying the numbers 8/9 x 8/8 = 64/81. If it had been
a true major Third, the ratio would have been 64/80, which is the same as 4/5,
as will be found by dividing the two numbers by 16. Although the old Ditone did pass for a Third in melody, it would not bear
the test in harmony. Every ear found it to be a harsh discord. The ear is so
much more delicately organised than the eye, that
even a hundred and sixtieth part of difference in vibrations, in one second of
time, has a rough and unsatisfactory effect, which every ear can distinguish;
whereas the quickest eye cannot distinguish, or count, more than twenty-four vibrations
in the same brief period. The delicacy of the one organ is quite as eight to
one of the other.
The improved major Third of Didymus and of Ptolemy
consisted, like our own, of two tones, the one major and the other minor: 8/9 x
9/10 = 72/90 =4 /5. Then the limma being
changed into a major semitone, made a true Fourth 4/5 x 15/16 = 60/80 = 3/4.
And now as to the discordance of the minor Pythagorean
Third, which must also be proved; for there is nothing like proof to fix
anything as a fact upon the memory. It consists of a limma and
a major tone : 243/256 x 8/9 = 1944/2304 = 27/32. Twenty-seven to thirty-two
are indifferent proportions that carry discord with them. They are neither
multiple, as 2, 4, 8, 16, 32, nor super-particular, i.e.,
one number is not the unit, or one particle above the other. They want the
comma to make them super-particular and consonant. The ratio is identical with
our imperfect minor Third of today, as between D and F, when the
scale has been tuned for the key of C; because it has then a minor, instead of
a major tone in it: 15/16 x 9/10 = 135/160 = 27/32. This defect was
inherited from Claudius Ptolemy’s scale. The true minor Third consists of a
major tone and a major semitone : 15/16 x 8/9 = 120/144 =5/6.
One of the musical laws of Pythagoras was, that, to be
concordant, all ratios must be either multiple (pollaplasioi),
like the Octave, 2, 4, 8, or like the Twelfth, 3, 9, 27, 81, or else they must
be superparticular (epimorioi), as 3 to 2, 4
to 3, or 5 to 4. This doctrine is referred to, among others, by Aristotle, in
his 41st Problem of Section 19. We have every reason to suppose it to have been
derived among other laws, from Egypt, because, although it was held as a maxim
by the school of Pythagoras, it was very imperfectly acted upon either by him,
or by his disciples, for a full 500 years after his death. Therefore, his
followers could not have regarded it as a really essential principle in music,
and as a law of Nature in the division of a string, or of a column of air
enclosed in a pipe. If otherwise, they acted too inconsistently in having
admitted only the Octave, the Fifth, and the Fourth, as simple consonances.
They should have included intervals in the ratio of 5 to 4, and 6 to 5, which
would have added the major and minor Thirds to their scales in a consonant
form. When Claudius Ptolemy followed out their doctrine, and so brought true
major and minor Thirds into his scales, he twitted the followers of Pythagoras
with their inconsistency in that respect. (Ptolemy, lib. 1. cap. 6.)
Neither the Octave, nor any interval within the
Octave, can be divided into equal parts. The most consonant and the nearest to
equal division of the Octave is into a Fifth and a Fourth, and the ratios
of both are super-particular, 2/3 and 3/4 = 6/12 = 1/2. The Fifth must, in like
manner, be divided into major and minor Thirds, 4/5 x 5/6 = 20/30 = 2/3. The
best division of the Fourth would be by the Harmonic Seventh, making from G to
C 6/7 x 7/8 = 42/56 = 3/4. The major Third would be into major and minor tones, 8/9
x 9/10 = 72/90 = 4/5.We lack the divisions of minor Third, and of
major tone, in our adopted Greek scale, but we divide the minor tone into our
two semitones, 15/16 x 24/25 = 360/400 = 9/10.
The first Greek who is known to have carried out the
doctrine of super-particular ratios into all his scales is Didymus. He had been
preceded by Archytas, and by Eratosthenes, but they did so only in part.
Claudius Ptolemy followed after Didymus, but made the same one exception to
this true principle as did Eratosthenes, by retaining the old Pythagorean
Diatonic scale, among others, either out of respect for the name of Pythagoras,
or because it was in general use. Nevertheless, each offered improvements upon
it. Didymus wrote a treatise upon the differences between Aristoxenians and Pythagoreans, of which we now know only some extracts, quoted by Porphyry
in his Commentary upon Claudius Ptolemy.
As a scale designed for the Diatonic system of the
Greeks, that of Didymus had some advantages over Ptolemy’s arrangement, because both were intended for the minor scale. The difference
between the two is but slight, the intervals being the same, and the scale of
Ptolemy seemingly copied from that of Didymus, of which it is a mere
transposition. In every Octave, two minor tones are necessary, one being
required for each of the two Fourths, to make them consonant. Didymus placed
one of his minor tones between C and D, and the other between F and G, while
Ptolemy changed their places to between D and E, and between G and A, as we do
now. In this last interval Ptolemy broke through the Greek law of having a full
tone below Mese, or the key-note, but he could not make a novelty
by any other means. Didymus obtained a perfect Fourth from A to D, a perfect
minor Third from D to F, and a perfect Fifth from D to A. The imperfections of
these intervals in our adopted scale have been a great perplexity to modern
musicians.
But although Didymus had these advantages in a minor
scale, they were outweighed by disadvantages when the key-note was changed in
later ages from minor to major. To obtain due proportions for a minor scale,
Didymus had made the Fifth from C upwards, and the Fourth from C downwards,
both imperfect.
The advantages and the disadvantages of these two
systems, which have been ranked as No. 1 and No. 2, by mathematicians for our
present imperfect seven planet scale, will be best seen by placing them side by
side, reminding the reader that every major Third, Fourth, and Fifth must have
one minor tone, and but one, to be perfect.
In both scales, the disjunctive tone, A to B,
was necessarily major, according to Greek laws, but in the major scale of
C, according to Nature’s law, it ought to be a minor tone:
Scale OF Didymus.
9 to 8 - 16 to 15 - 10 to 9 - 9 to 8 - 16 to 15 - 10
to 9 - 9 to 8
A to B - B to C -- C to D - D to E - E to F - F to Gr
- Gr to A
SCALE OF PTOLEMY.
9 to 8 - 16 to 15 - 9 to 8 - 10 to 9 - 16 to 15 - 9 to
8 - 10 to 9
A to B - B to C - C to D - D to E - E to F --F to Gr -
G to A
The imperfections of the scale of Didymus are, that by
having placed two major tones together, (G to A, and A to B,) he made a false
major Third from G to B; also a false Fourth from G to C, because there was no
minor tone in it; also a false Fifth from C to G, because he had two minor
tones in it. Again, from B to D, and from E to G, are false minor Thirds,
because they are made up with minor tones instead of major.
The imperfections of the scale of Claudius Ptolemy
are, that from A to D is a false Fourth, from D to F a false minor Third, and
from D to A a false Fifth. Also, that he has two
different kinds of major Sixth, one from C to A, with two minor tones in it,
and another from F to D, with one minor tone.
If Nature were called in to judge between the two
mathematicians as to the true positions of major and minor tones, she would say
that the one was right in the one place, and the other in another. Her law
agrees with Ptolemy as to the intervals between C and D, and between D and E,
but she wills a major tone between G and A, and a minor tone between A and B.
The above scale, by Claudius Ptolemy, to which he gave
the name of “the tightly-strung Diatonic” (Diatonon syntonon), is the one adopted by the moderns. It
is, perhaps, the best that has been devised for keyed instruments upon the
inherently defective system of making a true Fourth from the key-note upwards.
Even by Greek laws, the tetrachords began on the second note. A singer, or a
fiddle player, may avoid the defects of a scale, but a pianoforte-player cannot
alter the tuning' of a note for any change of key. We are so thoroughly Greek
in our system of music that it seems hopeless now to get rid of the prime defect
of having the half of every Diatonic scale in one key, and the other half in
what is misnamed its subdominant, or just a Fourth above it. It is that Fourth
which makes our scale to be in two keys instead of one. Such is, therefore, the
scale in which we are immediately concerned; and, with all deference to the
Greeks, we may, perhaps, venture to look into its defects, as well as its
advantages. We have one infallible guide to test it by, though it has been but
little subjected to that kind of analysis. A thorough knowledge of our scale is
a first requisite for a composer to make good harmony.
The preceding figures will have shown that the two
tetrachords, B, C, D, E, and E, F, G, A, are equal; that their proportions are
identical, (16 to 15, 9 to 8, and 10 to 9,) and that the one follows
immediately upon the other in fact, that they are equal conjunct tetrachords; The following scale
of Nature will show that equal intervals, within two consecutive tetrachords,
cannot arise from one root in a Diatonic scale, because Nature’s Octave
scale diminishes proportions at each step, viz., a ninth, a tenth, an
eleventh, twelfth, thirteenth, fourteenth, fifteenth, and sixteenth parts of a
string.
That interval, from E to F, to which we give the name
of major semitone, is the interval between a major Seventh and its Octave, and
it therefore leads to its Octave, and makes F become the Octave and a new
key-note. Then G becomes Second to F as its major tone, and A, which should be
major, is lowered into a minor tone, to make it a Third to F. Thus the scale is
changed from C to that of F.
Instead of all this, the minor Third from E to G being
as 5 to 6, or 10 to 12, ought to have been divided by the true Harmonic F, an
Eleventh, making the intervals 10 to 11, and 11 to 12. It is the change of the
ratio of an Eleventh to a Sixteenth that brings F too near to E, and makes it
touch so closely upon E sharp, that we actually omit E sharp in our scale. But
E sharp is wanted in Nature’s scale to make a Fifth and a Fourth to the
Harmonic Seventh. The two very wrong notes in this scale of Claudius Ptolemy’s
that we have adopted, are F and B flat. The ear has always told that they are
defective, as will be farther shown.
G, the Fifth, retains its place either way, but A
ought to be a major tone above G. Then it would be a proper Second for the key
of G, and a Fifth above D. It has been altered for the sake of making it a
major Third above F, a Fourth above E, and a minor Third below C; but the
alteration takes it out of the key of C. Nature does not provide a minor
Third under her keynote, neither does she acknowledge such a relative minor as
A. For Nature’s relative minor to C, (if any scale can be so called,) we must
look a Third above it, to E. According to Nature, every minor scale has its
real key-note a major Third below it, so the keynote of A minor is F. In other
words, a minor scale is merely one that is made to begin on the Third of the
key. This will be seen further.
The law of Nature as to sounds is well known to
practical men, and very simple. When a string is moved by a gentle breeze, its
whole length is sounded, and, immediately afterwards, it divides itself into
its aliquot parts, with quicker and quicker vibrations. These more rapid, but
comparatively feeble vibrations overtake and mix with the slowly spreading
waves of sound produced by the vibrations of the whole length of the string.
When the velocity of the air is greatly increased, or, as we term it, when, the
wind blows hard, the string is fluttered into many sections, and these shorter
lengths move with multiplied rapidity of vibration to the whole length. This
sensation of fluttering in parts will be sufficiently familiar to anyone who
has carried an umbrella in a high wind. The sections into which the string
is then divided are caused by self-made nodes, or divisions, and these nodes
are nearly quiescent points, and all equidistant. The number of sections
increases as each division becomes shorter, while the pitch rises proportionably
to their diminution in length. This diminution is caused by the increasing
intensity of the wind. It is like the overblowing of a pipe, by which it is
made to produce very high notes. As the sections become less, the united sounds
become louder as well as more acute, because the higher the pitch the greater
the number of sections emitting it. Supposing a string to be thus divided by
nodes into sixteen parts, their pitch will be four Octaves above the
fundamental note produced by its whole length. An extraordinary part of this
arrangement of Nature is, that in every progression the whole of the nodes are
changed. Thus, from sixteen, it divides into seventeen equal parts, from
seventeen to eighteen, and so on.
So, too, when we blow into a horn, of
pipe of any kind, with gradually increasing intensity and rapidity, we
subdivide the column of air within the pipe, and raise higher and higher notes,
just as the wind acts upon the string. In a flute, which is blown almost at a
right angle to the column of air, and so the action of the breath becomes less
direct than if it were blown at the end, the player may still draw eight
different sounds from one fundamental note, or generator, without removing a
finger to shorten the column of air. The lower the note upon which he may
commence, the larger will be the number of Harmonics he can produce before
reaching the limit to possible increase of rapidity in breathing. The
sounds so produced have three names. They are called “Natural Notes” upon a
horn, and “Harmonics” upon a string; also, according to Helmholtz’s
nomenclature, “Overtones”, because they are above the tone produced, by the
whole length of a string.
These Natural Notes, Harmonics, or Overtones, rise in
the same order of succession as to musical intervals, from whatever fundamental
note they may be derived. They do not vary in their order because the pitch of
the fundamental note has been chosen high or low; and this may be proved, even
when some of the low sounds may be too low to reach the ear. The one proviso
for Nature’s scale is that the string shall be uniform in size and
quality, and the pipe be an open one.
For exemplification of these rising sounds the
following table is subjoined. The fundamental note selected is C, two Octaves
below C in the base staff, and the lowest C on a pianoforte. It is the C C C pipe of the open diapason of
an organ. It is still popularly reputed to be “16 feet C”; but neither 4, 8,
16, nor 32 feet C are now so long as their names represent them to be. Owing to
difference of scale and to elevation of pitch; also, perhaps, to insufficient
pressure of wind for pipes of enlarged diameter, a nominal “32 feet C” is now
about 28 feet 6 inches in length, with 15 inches in diameter, and “4 foot C” about
3 feet 7 inches long.
I have taken the pitch at 512 vibrations for treble
clef C, as the only proper standard for musical pitch; because Octaves are the
only continuously perfect intervals. Nature’s Octaves are always
multiplied by 2; as 2, 4, 8, 16, 32, 64, 128, 256, 512. It is to be hoped
that at some future time 512 vibrations will be made the standard pitch of
Europe, by whatever name, the note may be called. If the question of pitch in. England
had been left to the decision of the Royal Society, instead of the Society of
Arts, 512 would undoubtedly have been the standard English pitch. In the
Society of Arts, 512 was admitted to be the right pitch; but, for the
accommodation of manufacturers, who feared that their stock of instruments
might have been rendered unsaleable, the pitch of 528, exactly a quarter of a
tone too high, was carried by a majority, and thus a temporary divorce between
the science and the art of music was pronounced.
The French standard of 870 for A, and
so of 522 for C, is a curious specimen of legislation. Neither of the two notes
can be carried down two Octaves without fractions. Truly, we read of vibrations
divided into fractions, but the art of accomplishing it has not yet been
divulged. Where fractions are resorted to, the root is changed. The law excited
strong remonstrance among scientific musicians against le diapason normal malheureusement fixé arbitrairement. Handel’s tuning fork gives from 499 to
500 vibrations. That of Mozart, and that of Berlin in 1772, (according to the
report of the French Commission,) was 843 half-vibrations for A, instead of
853, which is the calculated pitch for A under the present system of tuning the
Sixth; or 864'1/3, if the true A, (a Fifth above D,) allowing 512 for C. The
later works of Haydn, and those of Beethoven, were composed for a pitch
approximate to 512.
Considerations for private interests need not prevent
the Society of Arts from giving notice of future change. The members know
what is right, but, influenced by good nature, have not yet acted up to their
knowledge. Such a reunion of art and science as might thus be made, would be of
at least equal benefit to art. If pianofortes can now bear a tension of 528,
(and more) they can also bear thicker strings, and so can produce a better
quality of tone at 512. The same rule applies to all instruments with
strings, whether of wire or catgut. The plea of extra brilliancy by high
pitch is a mistake; for brilliancy is not constituted by mere acuteness, but
requires the addition of richness of quality in the tone. The practical effect
now is, that the instruments in an orchestra are too thinly strung, and thus
richness of quality is sacrificed to acuteness. The violoncello has no longer
the full tone that Lindley produced. Old violins were not made strong enough to
bear the new tension, so, thinner strings must be resorted to. Thus, the works
of the great masters are now inadequately represented. It is a case in which
Germany and England should unite. In France, change must await the repeal of an
eccentric law.
The scale might be carried further, into
quarter-tones, but it is unnecessary to print it, because there is a simple
rule by which any one may tell what the interval will be, and it applies to the
division of all super-particular ratios, or such as differ only by one degree.
Nature makes no fractions, but doubles the numbers, and interposes the one and
only intermediate number. Thus, in the above division of the Fifth,
No. 3, which is in the ratio of 3 to 2 of CC, No. 2, she doubles the
ratio, viz., 6 to 4, and interposes the intermediate 5. Then, in the next
Octave, this Fifth is divided into 6 to 5 and 5 to 4, minor Third and major
Third All odd numbers are new sounds; all even ones have before appeared in the
Octave below. The numbers of the Harmonics are of importance in many ways.
First, each indicates its proportion to the whole string, so No. 5 is a fifth
part of the length, and No. 27 a twenty-seventh part, vibrating twenty-seven
times as fast as No. 1; then, by multiplying the 32 vibrations of No. 1 by 27,
we ascertain the vibrations of the latter to be 864 per second of time, or just
as they stand in the table.
Again, multiply any number by 2, and we find its
Octave; multiply by 3, for its Fifths though an Octave too high; multiply by 5,
for its major Third Take the ratio of one number 'to another, as 21 to 14.
These are as 3 to 2 ; therefore, the notes they represent are at the interval
of 3 to 2, or a true Fifth. Take 9 to 12, or 12 to 16, the ratios are as 3 to
4; therefore, either pair is at the interval of a Fourth. If 15 to 18, a true
minor Third; and so on. Every number thus carries its musical ratio to all the
rest.
These are mere hints of the value of the scale of
Nature, all evident upon the surface. It is for the musician to point out its
deeper meanings.
And now to try our adopted scale by this most ancient
of all scales, and the one test of right and wrong. We find neither F, nor A as
we tune it, in the Harmonic scale, when C is the root, because they belong only
to a fundamental F. But we have the scale of G intimately connected with the scale of C. If our A were tuned a comma of
Didymus higher than it is, viz., as a major tone instead of a minor tone above
G, it would agree with Nature’s No. 27, thus proving the scale of Didymus to be
correct at that point. Ptolemy has mathematically calculated a Fourth above,
and a Fifth below C, where no such intervals come from the root; and he has
made the imported scale of the subdominant F more perfect by one degree than
that of the true key-note. For instance, F has its Sixth (D) a major tone above
its Fifth, although C, the nominal key-note of the scale, has it not. Transfer
the name of key-note to F, and we may derive every interval of this so-called
scale of C from F, except the B natural. As to B flat that is from a third root it belongs neither to C nor to F.
Nature’s Octave scale agrees to this extent with the
Greek, and therefore with our own, that each may justly be said to consist of a
disjunctive or major tone immediately above the key-note, and then of two
conjoined tetrachords or Fourths. From C to D is the major tone, and from D to
G and from G to G are the two Fourths. The difference is in the filling up of
those two Fourths. It has been said already that F and B flat are two
essentially Wrong notes for the key of C. Also, that A should be a major tone
above G, instead of minor, as it now is; and that E sharp has been omitted in
our scale only because we have a wrong F brought too close to it. Our F is only
a 64th part of a string above E sharp, and is a 33rd part below the F of
Nature. Again, if we had the true instead of the artificial B flat in our
scale, the semitone that we omit above E would harmonize as a true Fifth above
it. Our B flat is just as much above the real note as our F is above the true
semitone to E. We omit three Diatonic notes out of eight, viz., Nature’s
Fourth, Sixth, and Seventh; for A is but one of the semitones between the Sixth
and Seventh in Nature’s scale, and it ought to be a true Fifth above D. Our B
natural would then be the eighth tone in the scale, if the key-note were still
counted as No. 1, and we admitted eight, as in Nature.
The special disadvantage of our adopted F and B flat
is the impossibility of having more than four consecutive notes in one key
while we include them. Even to have four, we must begin with the major Seventh,
as B, C, D, E. Our B flat belongs neither to the key of C nor that of F; for,
just as there is no such Fourth as F from the root of C, so neither is
there any such Fourth as B flat from the root of F. The Harmonic B flat that we
omit has the major-toned A (No. 27) as its semitone, on the one side, and the B
natural of our scale (No. 15 or 30) as a tone, on the other side, to divide it
from the Octave. Its ratio of 7 to 6 of the Fifth makes it the interval next in
the order of consonance to a minor Third.
And now as to the constitution
of CONSONANCE and DISSONANCE, two words which, although
they carry their own interpretations as “sounding with”, and “sounding apart”,
have, nevertheless, been misapprehended; and one of the two causes of
consonance has been but little taken into the general account.
Degrees of consonance depend upon the proportion that
coincident vibrations bear to those which “sound apart”. The unison alone is
perfect consonance, because therein only do all vibrations coincide. Their
simultaneousness is rigidly exact, whether sounded upon the unison-strings of a
pianoforte, or upon the many instruments of an orchestra, with their varied qualities
of tone. Only in intervals is there any intermingling of coincident and
non-coincident vibrations. The unison is not an interval.
In order to abbreviate explanations, I refer to the
Harmonic scale at p. 217. Nos. 1 and 2 are an Octave apart. The first has 32
and the second has 64 vibrations per second of time. Therefore, No. 2 vibrates
as 2 to 1 of No. 1, and the first of every two vibrations of No. 2 coincides
with one of those of No. 1, while the remaining 32 of No. 2 “sound apart”
Again, Nos. 2 and 3, or double C and double G, are at tbe interval of a Fifth, and No. 3 vibrates 9,6 to the 64
of No. 2 or in the proportion of 3
to 2. The first of every two vibrations of No. 2 coincides, with the first of every three vibrations of
No. 3. So, there Are still but 32 coincident vibrations. Divide 64 by 2, and 96
by 3 to prove it.
One more example from Nos. 3 and 4. Here the total
number of vibrations is 96 to 128, but it is the first only of every three of
the one that coincides with the first of every four of the other. Therefore,
the number of non-coincident vibrations has progressed, while the original
number of 32 coincident vibrations has remained stationary; For that reason the
interval of the Fourth, or 4 to 3, is less consonant than that of the Fifth, or
3 to 2; just as the interval of the Fifth, 3 to 2, is less consonant than that
of the Octave, 2 to 1.
This natural law may be carried throughout the scale,
wherein dissonant vibrations increase, between consecutive numbers, at every
ascending step, while the consonant remain stationary. So the lower the two
numbers, the more consonant the interval. Still, it is a necessary proviso for
consonance that the sounds be derived from one root, as in this scale.
To take a last example from 15 and 16. They represent
the interval of a major semitone in every Harmonic scale. Here it is from b to
c. The numbers of vibrations are 15 times 32 of the one, to 16 times 32 of the
other. But as only the first of every 15 coincides with the first of every 16,
there are still but 32 coincident vibrations to leaven the mass of dissonance.
So the ear pronounces the interval from b to c, when simultaneously
sounded, to be exceedingly harsh and disagreeable. Nevertheless, the two sounds
are absolutely required for melody.
Hence follows a rule, that, whatever may be the
aggregate number of vibrations in a second of time from the fundamental note,
or entire length of a string, whether it be of such a length as to give 32, 33,
132, 133, or any other quantity, the same will be the number of consonant
vibrations between every two succeeding sounds of the scale. The intervals
follow invariably in the same succession, and are, therefore, represented by
the same numbers in every Harmonic scale. Hence any two numbers indicate the
proportions of an interval, just as every one number indicates its proportion
to a whole string.
Again, a second rule. Consonant vibrations are equal
to the difference in the total number of vibrations between every two
succeeding sounds, for just as 32 is the number of consonant vibrations in the
fundamental sound of this scale, so 32 is the difference between the vibrations
of every two succeeding numbers throughout the scale. If the same interval be
taken an Octave higher, the same proportion is observed, but the vibrations are
completed in half the time. Thus in the Octaves, 1 and 2, with 32 and 64 vibrations,
and 2 to 4, with 64 and 128; the vibrations of the later are doubled in
rapidity as they are in number. So they only perform in half a second of time
what the others do in a second.
Coincident vibrations are strengthened beyond others
by their perfect agreement, just as in the case of two hammers striking at the
same instant. The united sound is then louder than if the blow of the one
were to follow immediately after that of the other.
Coincident vibrations, having thus a superior power,
mark a musical rhythm combining sounds of different pitch. It is this
rhythmical coincidence which constitutes the charm of harmony in its different
shades, for harmony has always a certain amount of dissonance embodied in it.
The unison alone is free from all dissonance. Rhythm is the first in order of
the pleasures derived from music. It suffices wholly for the savage, with his
monotonous tom-tom beats; and, except as to the Harmonic sounds evolved, it is
the only gratification that the ear can receive from such instruments of
percussion as yield but a single note, such as a drum, cymbals, or castanets.
In harmony, we enjoy the effects of rhythm enhanced by a combination of various
sounds that differ in pitch, and we derive further pleasure from the varied
qualities of tone that are produced by the many instruments of an orchestra.
The due appreciation of so many simultaneous sounds is a reward reserved for
those who have cultivated their powers of hearing. A peasant will better understand
the single sound of a fiddle or of a flute. Some ears remain enclosed by the
perpetual sugar of successive unisons, while others have a greater appreciation
for varied harmony. Of the latter, some have also a taste which indulges
largely in an admixture of spice, in the form of discords.
The rhythm of coincident vibrations between two sounds
is often audible in the separate form of a third sound. The conditions are,
that the vibrations of the two originating sounds shall be
sufficiently rapid, and they must, therefore, necessarily be high in the
scale. If otherwise, they will not admit of consonant vibrations in sufficient
number within a second of time to form themselves into an audible musical note.
If too few, the resultant tones are indistinguishable from the general sound.
Another condition is, that the two primaries shall be sufficiently loud to
bring out the feeble sound of the resultant tone. A few examples of these will
be cited from practical experience in the sequel.
The second source of consonance to which I have
adverted is in the Harmonic sounds which follow immediately after the notes of
pipes, of strings, and of voices, and which thus serve to enrich their tones.
If two sounds be combined, the lower will produce greater effect, and this is
particularly manifest in the case of the wider consonant intervals. Thus,
between Nos. 1 and 4 of the Harmonic scale the interval is a double Octave.
When No. 1 is sounded, it throws out its Harmonics, 2, 3, 4, 5, 6, and they enrich
the consonance with No. 4. Upon keyed instruments, Octaves are usually the only
intervals thus enriched, because, in all cases, Octaves are tuned perfectly,
but, in too many cases, other intervals are tempered, i.e., put either a
little, or not a little, out of tune. Unless the tuning be perfect, Harmonics
militate against, instead of strengthen consonance.
I have been thus minute in detailing the causes of
consonance and of dissonance, because a theory as to their partial dependence
upon a fixed number of vibrations has been propounded by the learned Helmholtz,
Professor of Physiology in the University of Heidelberg. His view has been
widely disseminated through Lectures on Sound, delivered by Professor
Tyndall at the Royal Institution of Great Britain. The lectures have been
published, and having reached a second edition, in which this definition is
repeated, the objections to Helmholts’s view require
to be pointed out. It is the more necessary, because the lectures have been
largely adopted as authoritative upon sound, just as might have been expected
from the varied knowledge and the high reputation of its author.
Professor Tyndall says: Beats, which succeed each other at the rate of
33 per second, are pronounced by the disciplined ear of Helmholtz to be in
their condition of most intolerable dissonance.
In order to represent this theory, derived from
Helmholtz, in the fairest way, I extract one of the paragraphs from his Tonempfindungen. The original words are at the foot of the
page, and the following is a very literal translation:
The interval, b3' c", gave us 33 fluctuations in
a second of time, which make the united sound very grating to the ear. The
interval of a whole tone, bb1 c2, yields nearly double the number, but
these are much less grating than those of the first-named narrow interval.
Finally, the interval of the minor Third, a' c", should, according to
computation, yield 88 fluctuations in the second; but, in fact, the latter
interval allows us to hear scarcely anything of the roughness which the fluctuations
of the closer intervals produce. Now, it might be supposed that it is
the increasing number of fluctuations which obliterates the impression, and
makes them inaudible. For this supposition we should have the analogy of the
eye, which is likewise no longer able to separate a series of quickly following
impressions of light when the number is too great. Take, for example, a burning
coal swung round in a circle. When it describes a circuit from 10 to 15 times
in a second, the eye imagines that it sees a continuous fiery circle. So, also,
with the disk of colours, the appearance of which is
known to most of my readers. When such, a disk rotates more than 10 times in a
second, the different colours on it are blended into
one fixed impression of their mixed colour. It is
only by very intense light that quicker changes of the various fields of colour must take place [to be distinguishable] 20 to 30
times in a second. Thus, in the case of the eye, a similar phenomenon takes
place as with the ear. When the change between irritation and rest takes place
too rapidly, the change is obliterated in the perception, and rest becomes
continuous and uninterrupted.
But we may convince ourselves in the case of the ear,
that the increase in the number of the fluctuations is not the only cause of
their obliteration in the perception. Thus, when we passed from the interval of
a semitone, b3' c", to that of a minor Third, a' c", we
have not only increased the number of the fluctuations, but also the width of
the interval. But we may also increase the number of the fluctuations without
altering the interval, by transposing the same interval into a higher region of
the scale. If, instead of b#' c", we take the same two notes an Octave
higher, we obtain 66 fluctuations, and if yet an Octave higher, even 132
fluctuations, and these are actually audible in the same manner as the 33
fluctuations of b#' c", though indeed they become feebler in the very high
Octaves.
I have quoted Helmholtz’s words at full length, to
show how the second part of his argument militates against the first. In
the second part, he gives a case in which 33, 66, and 132 fluctuations are
equally dissonant; and that alone should prove that dissonance follows this
interval, and does not depend upon 33, 66, or 132 fluctuations. But Helmholtz
has mistaken the character of these fluctuations, and to that cause must also
be attributed the indefinite name he has given them. They are nothing but the
coincident and consonant vibrations. It is strange that he should have so
mistaken them as attribute dissonance to consonant vibrations, instead of to
the exceeding number of dissonant vibrations that are mixed in the interval
from b# to c.
That I may not misrepresent Helmholtz, I again give
his words. At p. 258, he says: “The number of fluctuations within a given time
is equal to the difference in the total number of vibrations which the two
sounds execute in the same time.” That is a precise definition of consonant
vibrations, and it can be of no other. The same number runs throughout a scale
in more or less rapid succession, whether the interval be Octave, Fifth,
Fourth, Third, or any other.
The mistake in the character of fluctuations has led
Helmholtz to propound a new doctrine as to the cause of resultant sounds, to
which I shall have occasion to refer hereafter.
This eminent acoustician did not sufficiently regard
the musical bearings of the Harmonic scale when he proposed to lay a basis for
the theory of music. That part of the subject has been too
much neglected by many writers on music. Helmholtz, through his system of
numbering by overtones instead of by the lengths that produce them, has missed
the advantages that the proportion-numbers of the scale would have conferred,
and has himself been led into such slips as to attribute to cc and dd 18
and 20 fluctuations, instead of to dd and ee.
As only the ninth and tenth vibrations coincide in the example which he has
given, the numbers must be our 9 and 10, or their doubles. C cannot have 18,
neither can D have 20 fluctuations, when the fundamental note throughout the
book is C C C, at the
German pitch of 33 vibrations.
For the reasons above given, I demur equally to the
doctrine in Professor Tyndall’s Lectures, on Sound, that, while dissonance is
at its maximum when the beats number 33 per second, it lessens gradually
afterwards, and entirely disappears when the beats amount to 132 per second. If
the full length of the string be about four feet, and give 132 vibrations,
there will be 132 in every following interval, consonant or dissonant.
Again, writers upon the science of music have for a
long time assumed as an admitted fact, that the numerous sounds which result
from the Harmonics of a string, or pipe, are not only emitted collectively and
superposed, but also simultaneously with those of the entire string. There
would indeed be a jargon if it were so let any one fancy half the keys of a
pianoforte down at once. Then, following out this theory, they attribute all
the various qualities of tone inherent in musical instruments, whether by wind,
by string, or by percussion, to differences in their Harmonics.
So very general has been the submission to these
assumed laws, down to the present time, that some may be astonished that I
should throw even a doubt upon them. Nevertheless, both the eye and the ear
give evidence against such doctrines. The test of the ear is within everybody’s
reach.
For instance, strike one of the lowest keys upon a
grand pianoforte smartly, and raise the finger instantly, so that the damper
may fall heavily upon the string. The harder the damper, the more patent will
be the fact that the Harmonics are not simultaneous, but consecutive. Each
successively rising note may be identified by a cultivated ear, upon an old
grand pianoforte, and even the uncultivated can distinguish the progressively
rising sounds, and that the highest note of all is the last.
This order would be reversed if the sounds were
emitted simultaneously, because, the higher the note, the sooner will its rapid
vibrations be completed. To prove it, touch a base and a treble string of a
pianoforte at the same instant.
Again, as to the Harmonics produced by the human
voice. Regnauls recent’t experiments upon propagation of sound through long water pipes may be cited to
establish the same order in their succession. The results of these experiments
are published in the Appendix to Professor Tyndall’s Lectures. The following is
an extract:
V. Experiments made with waves produced by the human
voice and by wind instruments have demonstrated these principal facts. Acute
sounds propagate themselves with much less facility than grave sounds. In very
long conduits, to hear well, it is necessary to employ a baritone; the
fundamental sounds are heard before the Harmonics, which then succeed each
other in the order of pitch. The propagation of the sound changes its timbre,
which is due to the admixture of the Harmonic sounds. In very long conduits, therefore,
a tune embracing a certain extent of the gamut would change its character.
These long conduits are the best proof, because the sounds are concentrated by
them.
So far for the ear, and next as to the eye. Not only
may a quick eye see the diminishing nodes upon a pianoforte string when it
changes its Harmonics, but Kundt’s experiments have proved them to
demonstration. He strewed the light dust of lycopodium within a glass tube, and
made the glass emit its various Harmonic notes by employing slower or quicker
friction. His experiments were exemplified by Professor Tyndall in his fifth
lecture, and were therefore witnessed by large audiences, composed of those who
take an interest in science. With every ascending sound, the dust was seen to
arrange itself into a greater number of. equal divisions. The length of every
section in the tube was changed just as every sound was changed. Indeed, it
might have been predicted; because Harmonics are only produced by aliquot parts
of a string, or of a column of air. Every division of a string into equal parts
will produce an Harmonic note, but the scale must teach where to place it.
Thus, both the ear and the eye, assisted by the pipe,
the string, and the voice, bear testimony against the simultaneous projection
of Harmonics.
As to the duration of sounds emitted, one important
cause has not been sufficiently taken into account. It is the
after-current which follows upon every displacement of air, however minute that
displacement may be. The vibrations of the air thus continue, as in echoes,
after the exciting cause has ceased. The longer the string, the wider is its
range of vibration; and, therefore, the greater the disturbance. The effect of
the displacement is felt on a grand scale in the after-current which accompanies
the discharge of a cannon. Not only the concussion, but also the rush of air,
are sensibly felt by all who are behind or near to it. We have again the best
practical evidence of the sound-waves which pervade even the seeming stillness
of the air, when we hear them concentrated and intermixed within the hard and
polished windings of a shell, by raising it to the ear.
And now, as to the theory which has been supposed to
account for difference of tone in numberless musical instruments.
Professor Tyndall says: It is the
addition of such overtones to fundamental tones of the same pitch which enables
us to distinguish the sound of the clarionet from
that of a flute, and the sound of a violin from both. Could the pure
fundamental tones of these instruments be detached, they would be
indistinguishable from each other; but the different admixture of overtones in
the different instruments renders their clang-tints diverse, and therefore
distinguishable.
In the first place, a flute, a pianoforte, a violin,
and a hautboy, have the same Harmonics; but very different are their tones. In
the second place, pure fundamental tones are always detached in harmoniums,
because they have no audible Harmonics. This is perhaps owing to their being
made with tapering springs. Yet different qualities of tone are sensibly
produced from the different stops of harmoniums, and every ear can distinguish
between them. Again, take three wooden open pipes of an organ, of equal length,
but, one of a square shape, the second with the proportions of 3 to 2 in
superficies, and the third of triangular form; they have the same Harmonics,
but all differ in tone. If facts of this kind cannot be gainsayed,
surely the two theories must fall together.
I here touch upon acoustics only so far as they are
strictly related to music, and thereby run into my path. Upon other, even
allied branches, I have nothing now to say.
The practical range of the ear for adequately
distinguishing musical sounds does not far extend beyond the seven Octaves of a
pianoforte, or else more notes would have been commonly added by the
manufacturers. An eighth Octave gives very indefinite sounds to most ears, and
even the extreme notes of the seven Octaves are not easily distinguishable
unless their Octaves are sounded with them, to make them definite. The
advantage of an eighth Octave consists in this, that it increases the quantity
of tone, and gives the richness of its Harmonics to the others.
The six-octave scale of Nature is as follows: FIRST, the
note and its Octave only. SECOND OCTAVE, divided into a Fifth and a
Fourth, afterwards providing an equal number of intervals for each of the two
divisions. THIRD OCTAVE, divided into four Thirds, of which we employ
only two, and change the character of the lesser two, by having omitted the
Harmonic Seventh that divides them. FOURTH OCTAVE, eight tones of
gradually diminishing interval, of which we employ only the largest two and the
least, but entitle the least a Diatonic semitone. FIFTH OCTAVE, the
same eight tones as before, with their eight intermediate semitones. SIXTH
OCTAVE, tones, semitones, and quarter-tones.
The Harmonic scale was only developed during the last
century, and was scarcely thought of in the theory of music until the present.
The discovery which led to its formation was made by two graduates of Oxford,
about the year 1673. It was communicated to Dr. John Wallis, the celebrated
mathematician, in 1676; was first made known by him in the English edition of
his Algebra, in 1685, and subsequently in the Latin edition of his Mathematical
Works, in 1693.
Dr. Narcissus Marsh, founder of Marsh’s Library in
Dublin, and an exemplary prelate, who was successively Archbishop of Dublin and
of Armagh, was residing in Oxford in and before 1676. Dr. Marsh was a great
lover of music, and especially of part-music, both vocal and instrumental.
These two branches were then much cultivated by members of the University, and
Marsh’s chief relaxation was in private concerts with certain of them, either
at his own, or at their rooms. In 1676 he informed Dr. Wallis, the Savilian Professor of Geometry, that about three years
before that date, two of his friends, William Noble of Merton College, and
Thomas Pigot of Wadham College, had discovered a means of producing, at
command, the Harmonics or natural notes from a vibrating string, and this to
all appearance simultaneously, and without intercommunication.
Before that time, little seems to have been
known beyond the facts that, if two strings are tuned in unison, and the
one be struck at no great distance from the other, the second string will sound
with the first; and, secondly, that the wind will produce weird sounds from the
strings of a harp exposed to its effects. The same amount of information was
shared by the ancient Greeks, and, among the earlier modems, by St. Dunstan.
The natural notes of a trumpet, or of a horn, could
not be measured; therefore it is of some importance to have discovered that, if
one of the aliquot parts of a string be touched very lightly, while the string
is under the friction of a bow, it will divide itself into nodes, and give the
Harmonic, instead of the fundamental, notes.
It has proved to be of more importance than Dr. Wallis
seems to have anticipated; for, although he turns sensibly out of his path to
record it in his Algebra lest the remembrance should perish, he states it more
as a natural curiosity than as of advantage to science.
The discovery lay fallow for half a century, and was
then taken up by Dr. Brook Taylor, who was the first to publish analytical
researches into the vibration of strings. Thenceforward, successively, by Bernouilli, Euler, Lagrange, d’Alembert, Riccati, Dr. Matthew Young, and by the illustrious Chladni,
down to the eminent mathematicians of the present century.
It will be an advantage to composers to consider the
difference of the several roots in every key, when they are writing for
performances in large buildings of resonant and Harmonic-giving qualities.
They must often wish to avoid the conflict of discordant Harmonics, since
grandeur of effect will, in a great measure, depend upon care in that respect.
Every semitone, and even every quarter-tone, in the Harmonic scale, may be used
in melody without preparation, and without going out of the key.
“The sense of harmony” says Sir W. Herschel, “depends
upon the periodical recurrence of coincidental impulses on the ear, and
affords, perhaps, the only instance of a sensation for whose pleasing
impression a distinct and intelligible reason can be assigned.” This passage is
quite the antithesis to the definition of Helmholtz, that coincidental impulses
may be causes of dissonance.
Harmony now means, both technically and truly, a
mixture erf concords with discords, both of which are included in the Greek
word Harmonia. If Herschel had intended consonances only, according to the
popular idea of harmony, he would have limited his definition to “coincidental
impulses on the ear, derived from a common root”.
Very different are the effects of the same interval in
two places. What singer has not observed how much more natural and agreeable it
is to sing a Fourth either up to, or down from, the key-note, than the same
interval taken from the key-note to a Fourth above it? The reason is that, in
the last case, he goes from one key into another. Again, the minor Third, when
in its right place, is one degree more consonant than the interval between the
Fifth and the Harmonic Seventh; but, if in the key of C, we sing or play
ascending C, E, G, Harmonic B flat, B natural, and C, we have an agreeable
melodic passage; whereas, if we substitute for Harmonic B flat, our B flat,
which is a minor Third to the G, and so play C, E, G, B flat, the ear
will not allow us to ascend further we are driven back upon A by the discord of B flat.
The system of subdominants is Greek, but not Natures.’
We sacrifice too much for the sake of making one extra interval of a perfect
Fourth from the key-note to its Fourth above, which Nature does not allow. Her
perfect Fourths are from the Second and Fifth of the key upwards, as from D and
G in the key of C. Defects of this kind were less forcibly observed by the old
musicians than now, because they did not test the s6ale by that of Nature; but
ears, ancient and modem, have always been protesting that these notes are
wrong.
The protest against the two notes, Fourth and minor
Seventh, commenced in very remote antiquity, we might say, in ancient Egypt, on
the assumption that Pythagoras derived his scales from Egypt, of which there is
hardly a doubt. It seems impossible to attribute the peculiarity of the Greek
Chromatic scale, in its passing down from the Octave, over the Seventh; and
then from the Fifth, passing over the Fourth; to any other motive than
that of avoiding those intervals which their ears told them were out of the
key. Again, the same two notes were picked out for omission in the Greek
Enharmonic scale, which, Plutarch tells us, had its origin in the desire of
Olympus to avoid the minor Seventh. It is also sure that Olympus, or whoever
invented that system, equally rejected the Fourth; for no ancient Chromatic or
Enharmonic scale includes either the one note or the other. Similar instances
may be noticed among the moderns, as in the universal rejection of the Seventh in the ascending minor
scale, and in the substitution of the major Seventh, which the ear has judged
to lead so definitely to the Octave, that it received from the French the name
of la note sensible or, in the words of Rousseau, parce qu'elle annonce la Tonique
et fait sentir le Ton. Again, in the rejection of
both Fourth and minor Seventh by the musical ears of the composers of
old popular ballads, Scotch and Irish. There are many English airs of the
same class, but they were not included in Popular Music of the Olden Time,
because the public voice would probably have attributed them to Scotland or to
Ireland; also because there was already too large a number of English airs for
publication in one selection. Other countries have tunes remarkable for the
same omissions. Mathematical science alone will not teach that the two
intervals are wrong, but the true science of music rests upon the investigation
and following out of the laws of Nature, and does not sanction any conflict
with those laws.
According to one learned writer upon the mathematical
branches of music, there was a true scale in use from the time of Monteverde or
Caccini. It had the F lowered by a sixty-fourth part, so really changed it
into E sharp, and it had the true A (27 to 16). He does not allude to the
Harmonic B flat which should have followed upon this arrangement, so as to make
true Fourths and Fifths with this semitone above E, because he there writes
only of a Diatonic major scale. But the partial adoption of the Harmonic scale
is confirmed by the ancient use of trumpets and horns without keys. They were
formerly very important instruments in out-door music, and could not be played
upon in any other scale than that of Nature until keys or valves were invented
for them. So it appears that the moderns have really retrograded, and have gone
away from Nature in the present scale. The reason for employing the semitone
above E, to make an F, was evidently to keep as near as Nature would permit to
the present scale. One grand objection to a tempered scale is, that it makes
false Harmonics, as well as false notes. Richness of tones depends much upon
Harmonics.
The mixture-stops of an organ are solely for the
purpose of supplying the Harmonics which are deficient in stopped pipes, and
there can be no grandeur of effect in an organ without those mixture-stops. But
there are organ builders who do not seem to know that such stops are to be
voiced softly, and organists who forget that they are only to be used with the
full organ, so that their tones may be covered by the volume of other sounds.
If made prominent, they produce a disagreeable, instead of a grand effect.
The stopped pipe of an organ is merely a pipe with a
plug at the end, or cap upon it, so that the wind has to travel to and fro to obtain an exit at the open lip, or notch. The column
of air is thus doubled in length, and the note produced is therefore an Octave
lower than that of an open pipe. A clarionet is of
the nature of a stopped pipe, and although closed only at the end next the
mouth, the effect of lowering the tone by an Octave is the same. One foot in
length of the clarionet produces the same C as two
feet in length on a flute. Only two Harmonics can be produced from a clarionet, viz., a Twelfth, and another Twelfth above it the
latter, with difficulty, on account of its high pitch. The peculiar Harmonics
of the clarionet were first brought into notice by
Sir Charles Wheatstone, F.R.S. Professor Tyndall says, that the clarionet has the Harmonics 1, 3, 5, 7, by opening the
holes at the sides. But to do so is to change the fundamental note.
Professor Tyndall gives a useful second rule for
comparing intervals, only in terms that may not be understood by every reader
without a line of explanation. He gives the notes of the scale of C thus:
Names, . . ................. c, D, E, F, G, A, B, C.
Hates of vibration, ....1, 9/8, 5/4, 3/3, 5/3, 15/8,
2.
and then says: Multiplying these ratios by 24, to avoid
fractions, we obtain the following series of whole numbers, which express the
relative rates of vibration of the notes of the Diatonic scale:
24, 27, 30, 32, 36, 40, 45, 48;
To multiply the ratios, means to multiply each upper
number by 24, and divide by the under, as in the case of fractions. This rule
may be preferred by some to the one I have given at page 200, and, for
musical purposes, the one is as efficient as the other.
But, for those who are versed in mathematics, it
should be pointed out that the use of the logarithms of the intervals very much
simplifies calculations, as then all the multiplication, the bringing to a
common denominator, &c., is entirely dispensed with. The logarithms, in
fact, exactly represent to the eye what the intervals do to the ear, and we
have only to deduct or compare the logarithms on paper, just as the ear does
when the corresponding intervals are heard.
For example, taking two kinds of tetrachord: their
composition is at once clearly illustrated by the following simple statement,
in which, it will be observed, there is nothing but addition used :
This excellent mode of calculating intervals was
introduced long ago by French and German writers, and extended examples of its
use will be found in Dr. Pole’s admirable Diagrams of the Musical Scale,
which are incorporated with the Rev. Sir F. A. Gore Ouseley’s Treatise
on Harmony. The system has not been followed here; first, from the
wish to bring the explanations within the reach of those who may not understand
logarithms; and, secondly, because the division of a string into its
aliquot parts is of practical application, and, to many minds, it will convey a
more lively impression of a sound, than will a short row of figures.
And now, quitting the subject of calculations, I turn
to another of Natures’ musical arrangements. The Pythagorean doctrine of the
existence of certain vibrating sounds, some of which are too high and others
too low to reach the human ear, has received unexpected confirmation both
during the last and in the present century. The existence of sounds that are
too high for our hearing has been demonstrated by the discovery that, under
certain conditions, the union of two generates a third and much lower sound,
which is quite distinct from its two primaries. Next, that this resultant sound
may be obtained even when the two primaries are inaudible. On the one side,
these resultant tones are said to have been discovered in 1745 by a German
musician and able writer on music, named Sorge, but that the disclosure
attracted very little attention at the time. Then, that they were discovered
independently by Tartini, the celebrated fiddle player, in 1754, and, after
him, were called Tartinis tones. On
the other side, they are said to have been discovered by Tartini while studying
the violin in 1714, and that he had taught them to his pupils long before he
published his theory of them in 1754.
In an Analysis of Musical Sounds, with Illustrative Figures of the Ratios of Vibrations, by John Henry
Griesbach, these tones are thus defined : Resultant sounds are not audibly
produced by the combined sounds of a pianoforte, because the sound of a pianoforte
gradually diminishes from the instant of its production to its extinction.
For the audible production of resultant sounds by musical instruments, it is
requisite that the sounds be continuous and equal. They are produced audibly by
organ pipes, and by the metal reeds of harmoniums, also by many different
intervals when the strings of a violin or tenor are made to vibrate powerfully.
Tartini used to tell his pupils that their Thirds could not be in tune unless
they heard 'the low note' meaning the resultant sound. Resultant sounds may
occasionally be heard when two sounds are powerfully sustained by female
voices. Triangles, metal bars, and bells, not only produce their Harmonics
powerfully, but also resultant sounds.
To produce such tones audibly it is necessary that the
two primaries be sounded rather loudly, as well as continuously, and it is
expedient to select two notes of high pitch for the experiment. Some attention
may be required at first to single out the feeble resultant tone, but it will
be readily accomplished after a little practice. A guidance to the ear in early
experiments will be, that the note to be listened for may be predicted.
Harmoniums that have been carefully timed yield these
sounds much more distinctly than those which have not. The best way of hearing
them is upon one of Wheatstone’s symphoniums,
an instrument which is no longer manufactured, it having been superseded by the
concertina. The tone is produced by the same metal springs, but, instead of a
bellows, they are breathed upon through the half-opened mouth. By breathing into this instrument, and lightly stopping
the ears at the same time, the resultant sound is heard quite as distinctly as
the higher two. The tones pass through the mouth to the auditory nerve by
the Eustachian tube, therefore inside the drum of the ear. A further advantage
of this method is, that, practically, the springs do not yield Harmonics,
therefore there is no confusion of sounds. It is the deficiency as to Harmonics
that makes the harmonium an unsatisfactory substitute for the organ. The symphonium should be warmed, to diminish
condensation of the breath upon cold metal. When a symphonium cannot be obtained, try the harmonium or concertina.
The following are examples of resultant tones:
If the two primaries be e and g, which
are Nos. 20 and 24 of the Harmonic scale, and at the interval of a minor Third,
the resultant tone will be C, No. 4, two Octaves and a major Third below
the e.
If the same e, with c, the major Third below
it, or Nos. 20 and 16, be sounded, the result will be the same C, No. 4, as
before, but it will now be only two Octaves below c.
If we next try g with the
same c above it, Nos. 12 and 16, making the interval of a Fourth, the
result will be the same C, No. 4, as in the two former cases, but now it is
only a Twelfth below g.
If we transpose the order of g and c,
and take g as a Fifth above c, Nos. 16 and 24, the resultant
tone will be C, No. 8, one Octave above the other.
If we try a major Sixth, as g and e,
Nos. 12 and 20, the result will be C, No. 8.
If a minor Sixth, as
from e to cc above it, Nos. 20 and 32, the resultant tone
will be g, No. 12, the major Sixth below e.
It might have been supposed, from five of the above
examples, that all would have resulted in the true key-notes, had not the
last experiment disproved it.
Helmholtz changed the name of Resultant Tones to
Difference Tones, and his reason was that the resultant note is that which is
equal to the difference between the ratios of vibration of the two primaries.
That is true enough, but it does not account for their being audible beyond
others. Difference tones only add one more degree of discord to each set of
vibrations, and the above are all consonant to the upper notes. Therefore I
demur to Helmholtz’s new theory, and revert to that of Dr. Thomas Young, that
these are the reflected sounds of the consonant vibrations, which are also
equal to the difference between the two primaries. There is good reason for
their superior audibility; but it would be indeed difficult to find a reason
for the predominance of the others.
The two notes which constitute the above example of
the minor Third e and g, when referred to the preceding scale, are Nos. 20 and
24, giving 640 and 768 vibrations. The consonance and the difference are both
128, and if we look for 128 vibrations, we find them produced by C, No. 4 of
the scale. Therefore C is the resultant tone. Then taking the last of the
series, the minor Sixth, from e to cc, as another test, they are Nos. 20 and
32, with 640 and 1024 vibrations. The consonance and the difference are both
384, and that number indicates g. No. 12, as the resultant. All the other
intervals may be similarly proved. I would, however, suggest that the
difference between the two numbers in the Harmonic scale is a shorter test than
that of calculating the difference between vibrations.
I can but suppose Helmholtz’s new theories to be due
to the imperfection of the instrument which he employed for his experiments.
Thus, in Dr. Tyndall’s words, when treating on these resultant tones, we are
told that the sound incessantly varies between silence and a tone of four times
the intensity of either of the interfering ones. This is given with all the
emphasis of italics.
I have tried the experiment with the most delicate
instrument for the purpose, tuned perfectly for me, with cotton in my ears to
exclude all external influence, and neither by that means, nor by harmoniums,
by concertinas, or other, can I discover any intervals of silence. Furthermore,
I have appealed to the highly sensitive ears of Macfarren,
J. H. Griesbach, and others, but no one can distinguish them. Then surely they
are due to the peculiar character of the Siren which Helmholtz employed for the
experiment. And, possibly, the Siren is also to be held responsible for the
theory of the fluctuations. It seems hard to account for it upon any other
principle.
The Siren is a nondescript instrument, the tones of
which are produced by puffs of air through 12, 20, or 30 holes at one time. So
there are virtually 12, 20, or 30 instruments sounding at the same time, and
some of these are counteracting the effects of others. If two harmonium-reeds,
exactly alike, be placed side by side and sounded together, it is all but
certain that the combined tones of the two will have less power than those of
either, separately; If two tuning forks of the same pitch be sounded at the
same instant, near to one another, the sound of both may be neutralised by the manner of holding one at an angle to the
other. This is a well-known experiment, which I have often made, and one that
Professor Tyndall has largely illustrated in his lectures. It is easy to see,
says he, that the forks may so vibrate that the condensations of the one shall
coincide with the condensations of the other, and the rarefactions of the one
with the rarefactions of the other. If this be the case, the two forks will
assist each other. ... It is, however, also easy to see that the two forks may
be so related to each other that one of them shall require a condensation at
the place where the other requires a rarefaction; that one fork should urge the
air-particles forward, while the other urges them backward. If the opposing
forces be equal, particles so solicited will move neither backwards nor
forwards, and the aerial rest, which corresponds to silence, is the result.
Thus, it is possible, by adding the sound of one fork to that of another, to
abolish the sounds of both.
It is singular that the intervals of silence did not
arouse the attention of the great acoustician to the imperfections of the
instrument with which he conducted so many experiments.
Resultant tones had been much experimented upon in
England before Helmholtz gave birth to his theory, and they led to the
discovery, or rediscovery, that sounds might be too acute to affect the human
ear.
Sir Charles Wheatstone, LL.D., D.C.L., F.E.S., had two
very minute metal tongues made for him, of the kind used for concertinas and
harmoniums, but so minute that their exceedingly acute sounds
were inaudible separately, yet when blown together their graver resultant
sound was distinctly within hearing.
Our present Professor of Music in the University of
Oxford, the Rev. Sir F. A. Gore Ouseley, Bart., had
two very minute open pipes constructed; which were equally inaudible when blown
separately, but of which the resultant sound, two Octaves below the calculated
pitch of the lower pipe, was distinctly heard. A similar experiment was tried
with equal success by Mr. J. H. Griesbach, from whose work, already quoted, the
above account of these experiments is derived.
Instruments have been invented for testing the limit
of the human ear as. to the higher notes, and they show considerable variations
in different individuals.
In the case of exceedingly low notes, the sound waves
succeed one another too slowly to effect the necessary continuity by which the
auditory nerve must be excited in order to convey the impression of a musical
sound to the brain. If the vibrations are less in number than 16 in a second of
time, the ear is conscious only of separate shocks. If they exceed 38,100 in a
second, according to the recent calculations of Helmholtz, the consciousness of
sound ceases altogether. The range of the best ear covers about eleven Octaves,
but an auditory range limited to 6 or 7 Octaves is not uncommon. The sounds
available in music are produced by vibrations comprised between the limits of
40 and 4000 a second. They embrace 7 Octaves. The range of the ear far
transcends that of the eye, which hardly exceeds an Octave.
Experiments upon very low sounds were exhibited by the
late D. C. Hewitt, by the late Professor Donaldson of Edinburgh, but on the
largest scale by the present Oxford Professor.
Sir F. A. Gore Ouseley strained a wire of 64 feet in length, and regulated the tension so as to
produce C, four Octaves below C in the base staff When plucked aside, the note
was inaudible, and even the half-length was only to be heard by a few favoured ears, but the quarter-length of 16 feet, or the
lowest C upon a pianoforte, became sensible to all when put into vibration by a
bow. The experiments of Professor Donaldson were of the same character, and
with the like result.
These recent investigations have been turned to
account by, at least, one manufacturer. It became evident that horns of various
kinds might be made of such length in the tube, straight or curved, that
although no sound would be heard from its entire length, the player might take
up Natures scale at her fourth Octave, and so produce the eight Diatonic notes
within that Octave, and sixteen semitones in the Fifth; whereas, if he could
have sounded the whole length, he would have obtained but two notes in the first
Octave, and but three in the second. This has demonstrated the possibility of
effecting a great enlargement of the powers of instruments of that class,
subject to the one great drawback of their cumbrous size.
Thus the doctrine of the Pythagoreans, which was
adopted by Cicero, Pliny, Boethius, and generally in the middle ages, has been
unexpectedly verified by modern science.
THE MUSICAL INSTRUMENTS OF THE ANCIENTS10.- Difficulties of the subject.- Athenaeus’s incorrect account about the Hydraulic Organ—General names.— Magadis.— Sambuca.— Buxus.— Wind instruments.— Syrinx, or Pandean Pipe.— Pandura.— The Double Reed or Hautboy principle.— The Bassoon and Comet, or Como Inglese.— The Gingras.— The Bombos. —Roman Haut-boy-player.— Second principle: the Single Beed Clarionet.— The Shawm, or Chalumeau.— A Pythian game of Apollo and the Python.— Pythauli.— Chorauli.— The Box for Reeds.— Many materials for Pipes, and their names from countries and from special purposes.— Length of Arabian Pipes proverbial.— Egyptian Pipes many notes.— The Bombyx.— Third principle : the Pipe blown at the end.— The old English Flute and the Flageolet.— The Organ Diapason.— The Egyptian Pipe and Greek Monaulos and Kalamaulos.— Fourth principle : the present Flute.— The Photinx and Plagiaulos.— Egyptian Flute.— Phrygian and Berecynthian Pipes with homs at the end.— Elymos.— Scytalia.— Competitions of Pipers.— The muzzles round their mouths.— Bagpipe.— Fifth principle : the free Reed or Harmonium principle derived from China.— Sixth principle : Trumpets and Horns— Egyptian, Assyrian, Greek, Etruscan, and Roman.11.-Instruments of Percussion.—The Egyptian Sistrum.—Drum.— Dulcimers. — Timbrels or Tambourines. — Three kinds of Cymbals. — Oxubaphoi. — Lekidoi. — Acetabula. — Krotala. — Krembala or Castanets. |