200 Scientific Intelligence—Arts. 
-destined to produce the most powerful musical effects. A mechani- 
cian by profession, being a manufacturer of steam-engines in the es- 
tablishment of Chaillot, M. Isoard was led by an irresistible fondness 
for music to attend the lectures of M. Savart, and it is from that rich 
source of information that he has derived his knowledge of the theory 
of vibrations; and from listening to these fertile instructions on the 
application of such theoretical views that he has deduced the-possibi- 
lity of impressing on a string powerful vibrations, causing it to per- 
form the part of the reed of a wind-instrument. The novelty of the 
contrivance excited the surprise of the professor, and the extent to 
which it might be carried immediately struck his acute perception. 
The ingenious artizan, who had been his assiduous and attentive 
pupil, became his friend ; and I recollect with pleasure having been 
admitted by M. Savart to partake in his sympathies, and more than 
once I was a witness of the warm interest with which he was inspired 
by the undaunted mechanician who, in the pursuit of his object, aban- 
doned the sure resources of his profession, sacrificed every thing he 
had acquired by his toil, and sold piece by-piece his furniture and 
even his tools. The talented professor of acoustics warned his pupil 
of all the difficulties of his undertaking ; and it is only now after ten 
years of constant and expensive experiments, that he presents the 
feeble but interesting specimen of the effects which will one day be 
produced by the application of the new method of producing sounds. 
To convert the ordinary vibration of the string of a piano into a 
powerful sound of a wind instrument, all that M. Isoard does is to 
place under the strings a moveable case, divided into as many com- 
partments as there are different strings which he wishes to cause to 
vibrate. Each compartment communicates with a common port-vent 
by means of a valve. The air, compressed by double bellows, is 
stored in a special magazine ; and it is admitted at the proper time 
into each compartment by means of the opening of the valve upon 
touching the key. The emission of the air, thus introduced for the 
purpose of continuing and augmenting the vibration of the string, 
takes place through a longitudinal slit in which the string may be in- 
serted at will. We say intentionally, that the string struck by the 
air continues to vibrate; for M. Isoard, like his predecessors in 1790, 
has had to contend with the slowness with which certain strings com- 
mence their vibration ; like them he has been able to triumph over 
the obstacle, but by a very different means. The much more simple 
mechanism of the hammer which strikes the string, has been preferred 
by him to the very ingenious but very complicated apparatus which 
rubs the string in order to cause its vibration to commence. 
