Biography—Cagniard- Latour. 267 
when em 
for the clarionette equal to the pressure of the atmosphere, plus a column 
water of 30 centimeters. In order to extend these inquiries to the 
human larynx, it was necessary to find a person having-an opening in the 
_ trachea, and yet able to produce vocal sounds at will. After long search, 
wn experiments of Dr. Beaumont. In the same year he made 
known his chronometric balance, designed to measure the dynamic effects 
machines in motion. 
Next appeared a memoir on the alcoholic fermentation, of which these 
were the principal results : 
Ist. The yeast of beer is made up of little globular bodies, apparently 
som and capable of reproduction in two different manners. These 
md vegetable matters, those which serve as ferments and those which are 
ject to fermentation ? 
lard-Latour new resumed his researches upon vibrating bodies, 
tly be ed in producing a sound by causing a glass rod to oscillate 
wl tween two metallic columns. The peculiarity in the sound thus 
ed was that the number of vibrations indicated by it corresponded 
to one-half the synchronous number of simple oscillations of the rod 
: ntl © apparatus was arranged in such at each mo’ 
ay, kwards and forwards should produce two strokes of equal inten- 
7° alternate blows upon the two columu € experimen 
nstrating some new acoustic phenomena. In two pre- 
wl hogs Published in 1880 and 1881, upon the sounds produced by 
| Wee. &s turning with great velocity, he had shown certain facts rela- 
~ i; ™ musical tones produced by the friction of the axle of a wheel 
Wrolution, af vont Subsequently he conceived the idea that a solid of 
ound its a cylinder for example, arranged so as to turn vertically 
| (ing axis upon two eenter-holes, might give rise to pulsating sounds 
i ); although moving with a feeble velocity, provided it received 
from Cagniard-Latour an investigation on the action of 
* different kinds of wood enclosed in hermetically sealed glass 
