JF Ptak Science Books Post 2331
Fleeming Jenkin was a very considerable man with a huge range of interests and talents, along the lines of a William Thomson/Stanley Jevons. His main deal though and the place where he earned his keep was in engineering, and here he was virtuosic. I call him up now because of an article that appeared in the 1878 issue of Nature magazine, entitled "The Phonograph". The instrument was invented by Edison in 1877 (and patented in February 1878)--it was an extraordinary thing with great promise, though not so much in the ways we think of today. In any event, Jenkin was able to produce one for himself--to reverse engineer it--from descriptions he read of the machine in the newspapers, which is a big accomplishment.
What he set to do with it was impressive--he began to study the components of speech. And not just by audio comparison--he devised a method to make transverse sections of the recording wax so that they could be magnified and allow him to study the visual differentiations made by speech in the medium. Now that is very good--making the phonograph into a phonic graphing machine.
Here's the article, written by Alexander J. Ellis, as it appeared in the May 9, 1878 issue of Nature:
The Phonograph
Since writing my former letter on the phonograph {NATURE,
vol. xvii. p. 485) I have had the advantage of seeing some of
the work that Prof. Fleeming Jenkin is doing with his own
instrument, which must, I think, be more sensitive than the one
I examined. This work convinces me that the phonograph has
already risen beyond the rank of lecture illustrations and philo-
sophical toys, to which I assigned it in my last, and that it
promises to lay some permanent foundations for the more accu-
rate investigation of the nature of speech sounds. Prof.
Fleeming Jenkin, by a most ingenious arrangement, which I must
leave him to describe in his paper to the Royal Society of Edinburgh,
obtains vertical sections of the impressions made on the tin-foil
by the point of the phonograph, magnified 400 diameters. Some
of these original tracings I had the pleasure of seeing yesterday,
and they are full of interest. I have termed them "speech
curves." They differ considerably from the phonautographic
speech-ciu^es of Leon Scott and Koenig, which only succeeded
with the vowels, and from the logographic speech-curves of Mr.
Barlow, which only succeeded with the consonants, in so much
as they succeed with both. In such a word as tah, for example,
intoned rather than sung, but not simply spoken, as the vowel
would otherwise not last long enough for subsequent study, we
have first the " preparation," in which the curve gradually, but
irregularly, rises, then the "attack," where there is generally a
bold serrated precipice, with numerous rather sudden valleys ;
next the " glide " where there is a perfect tumult of curvatures
arising from the passage of voice through a continually changing
resonance chamber, producing a rapidly and continuously chang-
ing but indistinct series of vowel sounds, which gradually settle
down into the "vowel " proper. In the vowel, if well intoned^
the curve remains constant for a considerable number of periods,
beautifully reproducing itself, but, as the intoner becomes
exhausted, "vanishing" away gradually to silence, the distinc-
tive peculiarities of the curve disappearing one by one, till a
dead level is again reached.
Then Prof. Fleeming Jenkin subjects this vowel curve to
"analysis," reducing it to the separate "pendular" curves of
which it can be composed. This corresponds to determining the
"partial" tones {parzialtone, theilt'dne of Helmholtz, of which
all but the lowest are called oberparzialtbne, obertheiltone, and by
contraction obertone, whence the unfortunate English word over-
tones, which is constantly confused •w\\h. partials, thus assuming a
part for the whole) out of which the whole " compound" tone is
formed. The first two partials are much stronger than the rest,,
the second often stronger than the first (hence the frequent con-
fusion of octave ?), the others generally very weak, although ex-
ceptionally one of the higher partials may be stronger. As many
as five partials, as far as I remember, were traced out in the
analysis Prof. Jenkin showed me, which he had just received
from Edinbiugh. The results differ materially for different
speakers. Also there is a peculiarity in the "phase" with
which the different partials enter into combination. Helmholtz:
showed that this difference of phase would materially alter the
form of the curve, but would not alter the appreciation of quality
by the ear depending upon the actual partials and their degrees
of loudness alone.
The phonograph, as I have said, resembles rather a worn
" print " than a " proof " of the human voice. This means, of
course, that the delicate upper partials, on whichj all brilliancy
depends, are absent. In some respects this is advantageous
for the very elaborate inquiry which Prof. Fleeming Jenkin has-
instituted, for it enables him to catch the bold outlines on.
which genera depend, without being at first bewildered by the.
delicate details which give specific differences. Our speech
sounds are, of coiuse, individual, and what is recognised as the-
same speech sound varies in the same speaker within the limits
of its genus, almost every time it is used. We shall do muck
if we establish the genus. The extent of Prof. Jenkin's
researches, as he contemplates them, and the care with which
his initial experiments, tracings, and analyses have been con-
ducted, lead us to hope that we have at least got an instrument
which will enable us to solve the elementary problems of
phonetics that have hitherto almost baffled u?, although it is
not suited, as yet, to fix those delicacies of utterance which were
my own special object of investigation.
April 30 Alexander J. Ellis
"On the death of Fleeming Jenkin, his family and friends determined to publish a selection of his various papers; by way of introduction, the following pages were drawn up; and the whole, forming two considerable volumes, has been issued in England. In the States, it has not been thought advisable to reproduce the whole; and the memoir appearing alone, shorn of that other matter which was at once its occasion and its justification, so large an account of a man so little known may seem to a stranger out of all proportion. But Jenkin was a man much more remarkable than the mere bulk or merit of his work approves him. It was in the world, in the commerce of friendship, by his brave attitude towards life, by his high moral value and unwearied intellectual effort, that he struck the minds of his contemporaries. His was an individual figure, such as authors delight to draw, and all men to read of, in the pages of a novel. His was a face worth painting for its own sake. If the sitter shall not seem to have justified the portrait, if Jenkin, after his death, shall not continue to make new friends, the fault will be altogether mine."--Robert Louis Stevenson, in his introduction to Memoir to Fleeming Jenkin, 1901.
Comments