K. MECHANICS AND ENGINEERING. 413 



cing it to powder, and a brisk trade has already sprung up in 

 Germany in this article. The bones are likewise to be ground 

 and utilized in various ways, so that the entire animal blub- 

 ber, flesh, and bones will be put to economical purposes. 

 The carcasses of over thirty whales were heaped up on the 

 island at the time of the visit referred to, forming a red hill 

 of very considerable magnitude, visible at a great distance. 

 The proprietor stated that the factory would not answer its 

 expectations unless fifty whales could be taken every summer. 

 It was thought, however, that there would be comparatively 

 little difficulty in securing this number ; and, in fact, as we 

 learn from later advices, over sixty in all were captured dur- 

 ing the season. 2 A, December 24, 464. 



A NEW GUNPOWDER. 



Among the many practical applications of phenic or car- 

 bolic acid, not the least important is its use in the prepara- 

 tion of picric acid, a substance which, in combination with 

 potash and other bases, promises to'be of great value in the 

 arts. Although readily produced from other substances, car- 

 bolic acid appears to be the most desirable source of supply, 

 and only requires to be treated with concentrated nitric acid. 

 A combination takes place with a hissing noise, and results 

 in the formation of picric acid, in long lamellar crystals of a 

 beautiful lustrous yellow color, and of an intensely bitter 

 taste. Already used extensively in the preparation of dyes, 

 it is as an explosive, of peculiarly valuable properties, that we 

 now call the attention of our readers to it, as, when heated 

 suddenly to the proper degree, it decomposes with explosion, 

 and this peculiarity is iocreased when combined with an al- 

 kaline base. The picrate of potash is the most important in 

 this respect, and has lately been the subject of extended ex- 

 periment on the part of an eminent French chemist. This is 

 a salt of a beautiful golden yellow color, crystallizing in pris- 

 matic needles, and, while insoluble in alcohol and nearly so in 

 cold water, dissolves readily in fourteen parts of boiling wa- 

 ter. Heated carefully, it acquires an orange-red color at 572 

 Fahr., which it loses on cooling ; heated rapidly to 620 Fahr., 

 or brought in contact with red-hot bodies, it explodes vio- 

 lently. It is most readily prepared by the double decompo- 

 sition of a soluble picrate of soda, magnesia, or lime, and a 



