Mr. AuLen’s Experiments upon a Substance called Dapéche. 321 
like manner exhibits signs of electricity, by causing dry paper 
which has been rubbed with it to attract- pith balls. 
I made parallel experiments with equal duanik of Caout- 
chouc and Dapéche in the sulphuric, nitric, muriatic, and strong 
acetic acids, also with a mixture of nitric and muriatic acids : 
they. were performed in a temperature between 32° and 42° of 
Fahrenheit, and there was a striking similarity in the results. 
Nitric acid, even without the application of heat, dissolved both 
these substances almost entirely ; and on the addition of water to 
the clear solutions, copious precipitates were afforded, which, 
being washed and dried, mounted to uet one > half of the ori- 
ginal weight. - ee 
The precipitate from Casu hohé was dissolved. by jag | 
alcohol ; that from Dapéche nearly so: but alcobol produces no - 
effect u pon Caoutchouc itself, and only renders Dapéche. more 
elastic. E 
"The mixture of nitric and muriatic acidi did not appear to 
dissolve a any part of these substances; but they had evidertly 
undergone a change, and had increased in weight—the Dapéche. 
particularly: they no longer melted on exposure to im but 1 were 
converted into a dense coal. — . 
By distillation to dryness i in | glass re retorts, the following results 
_ were obtained : 
yd | Caoutchouc 100 sore ? 
A Jerownt pre MER oil containing no trace of scil E 
- 14 cubic inches of gas — — pea 2 
 Carbonaceous residuum - - j> ári 6 
VoL. VIII. 2T Dapéche 
