14 
BRITISH ASSOCIATION.— 1835. 
pressed. It was found, however, that the sounds of the longer tube, 
which also belong to the series of the shorter, were obtained with 
superior clearness, as E". E'". and A", and B". appeared to break 
into each other. 
Other experiments having shown that systems of tubes may, 
by certain methods of vibration, be forced to produce sounds not 
included in their natural series of harmonics, and it being pos¬ 
sible that the suppression of the proper vibrations of the shorter 
tube resulted not from the ordinary principle of interference 
but from being forced into unison with the longer one, Professor 
Kane endeavoured to obtain a system in which the whole series 
of neither tubes should be suppressed, but that certain notes 
should be absorbed from the series of each. In only one case did 
he succeed, but in that one the result is very satisfactory. A 
combination was made of this figure, in 
which the length of the path a . b. c. e. was 
21 inches, that of the path a. b. d. e. was a, \ _ 
18 inches. The series of the shorter tube ^ 
was F. F'. C". F"'., and of the longer D. D'. Ah D'h F". A". D n, . 
The waves being excited from the orifice e. the series of the system 
was D. F. D". F". A". C 1 ". Hence the notes F\ and C". had 
been absorbed from the series of the shorter, and the notes D\ and 
Ah from that of the longer tube: whilst the F. F'h and C ,n . of the 
one and the D. D r h and A", of the other tube maintained their place 
in the series given by the system. 
On the various Attempts which have been made to imitate Human 
Speech by Mechanical Means . By Professor Wheatstone. 
Professor Wheatstone gave an account of the various attempts 
which have been made to imitate the articulations of speech by me¬ 
chanical means. He described and repeated the experiments of 
Kratzenstein, De Kempelen, the Abbe Mical, and Mr. Willis of 
Cambridge. De Kempelen’s speaking-machine was exhibited in 
the course of the lecture, and made to pronounce many words and 
a few short sentences. Professor Wheatstone concluded with an 
analysis of the elements of speech founded on these and other inves¬ 
tigations, and pointed out the importance of the inquiry as con¬ 
nected with philology. 
On the Construction of Public Buildings in reference to the communi¬ 
cation of Sound. By Dr. D. B. Reid. 
Dr. Reid maintained, from numerous experiments made in the 
open air in the neighbourhood of Edinburgh, in which he w*as as¬ 
sisted by a number of gentlemen, and also from a comparison of 
his class-room with many other buildings, that any difficulty in the 
communication of sound in large rooms arises generally from the 
