INDIA-RUBBER, OR CAOUTCHOUC. 455 



The fluid obtained from the latter plant is dried in a 

 different manner, and constitutes the solid flat pieces 

 which are known as white Indian rubber. 



Caoutchouc possesses some peculiar and remark- 

 able properties, which, from the earliest period of its 

 being known in Europe, have been subjects of the 

 diligent investigation of some of the most eminent 

 chemists. It is the most pliable and elastic of known 

 substances, and so tenacious that it cannot be broken 

 without considerable force. It has always been a de- 

 sideratum with chemists to dissolve caoutchouc by 

 some means which would allow it to re-form, and to 

 assume different figures with the same facility as they 

 can be imparted when in its original state of fluidity. 



Within the last few years two solvents, which can 

 be abundantly and cheaply supplied, have been found 

 for caoutchouc, which, when evaporated, leave it un- 

 changed. By these means this substance is made to 

 be of extensive application. A thin coating of the 

 solution spread on any texture renders it impervious 

 to air or moisture ; while, at the same time, it can be 

 folded in as portable a form as before it had received 

 this preparation. Hence pillows and even beds are 

 formed out of bags thus made air-tight ; and these 

 being furnished with a small tube and stop-cock, may 

 be inflated at pleasure into soft elastic cushions. 

 Cloaks having their inner lining of this material are 

 found to be effectually water-proof. 



Mr. Faraday, of the Royal Institution, has fur- 

 nished an interesting paper in the 21st volume of the 

 Quarterly Journal of Science, &c. detailing his expe- 

 riments on some caoutchouc in its fluid state, which 

 had been obtained from the southern part of Mexico, 

 and was very nearly in the state in which it came 

 from the tree ; a slight film of solid caoutchouc had 

 formed on the surface of the cork which closed the 

 bottle. The juice was a pale-yellow thick creamy- 



