148 [April 20, 
mitted speech in an ordinary phonographic apparatus, or, preferably in 
connection with a variable resistance contact, electrically in a receiving 
telephone. : 
There can be no doubt, whatever, that this method will be found opera- 
tive in practice, since the engraving stylus, a pencil of light, is destitute 
of weight, and therefore offers no resistance to the free movements of the 
telephone diaphragm. 
C05 Instead of causing the voice, as in the ordinary form of phono- 
graphic or gramophonic apparatus, to act. mechanically on the record-sur- 
face, cause it to move a suitably focussed pencil of light over the surface 
of a photographic plate. A very complete record could thus be obtained, 
in which it would be possible to impress on the plate all the minute pecu- 
liarities of the overtones, on which the quality of the voice depends. In 
this manner there.could be obtained and preserved records of the voice of 
distinguished individuals. 
The photographic method just described would possess, among others, 
the following advantages, viz.: 
ist. The ease with which it could accurately reproduce in all their min- 
utise the tones involved in the production of articulate speech. 
2d. The readiness with which such a record could be magnified to any 
desired extent, thus rendering possible an increase in the amplitude of the 
reproduced vibration. 
3d. The aid such magnified, accurate sound-records wouldafford in the 
study of the same with a view, not only of ascertaining their peculiari- 
ties, but even with a view of being able to read articulate speech directly 
from the diaphragm record. 
CrnTRAL Hien ScHooL, 
PHILADELPHIA, April 6, 1888. 
Stated Meeting, April 20, 1888. 
Present, 14 members. 
President, Mr. FRALEY, in the Chair. 
Correspondence was submitted as follows: 
A letter from Washburn College, Topeka, Kansas, request- 
ing exchanges; on motion, ordered to receive Proceedings 
from No. 96. . : 
A letter from Prof. Joseph Prestwich, with change of ad- 
dress (Shoreham, Sevenoaks, Kent). 
~ A letter of envoy from the Meteorological Office, London. 
