M. Boussingault on the Constitution of Bitumens. 487 



Water was decomposed with extraordinary rapidity by a bat- 

 tery of this description, and also muriatic acid, the chlorine of 

 which bleached asolutionofsulphateof indigo in a fewseconds. 



Its effects on the animal system, as exhibited by Mr. Hem- 

 ming to the audience, were almost terrific. A rabbit recently 

 killed, an eel, and frogs were thrown into more violent mus- 

 cular action than I had ever previously witnessed *. 



The te7ision of electricity seems to be greatly increased by 

 this mode of charging the voltaic battery. 



BunhillRow, Sept. 15, 1836. 



XCl. On the Constitution of Bitumens. i?j/ M. Boussingault. 



M BOUSSINGAULT remarks, that bitumens, so abundantly met 

 • with on the surface of the earth, and the uses of which seem 

 continually to increase, have hitherto been but slightly examined, so 

 that, if we except the researches of M. de Saussure on the naphtha of 

 Amiano, we are still nearly ignorant of the particular nature of these 

 substances. 



It has always been admitted that the great combustibility of bitu- 

 mens is owing to their being chiefly composed of carbon and hydrogen, 

 and the water which some varieties afl'ord by dry distillation favours 

 the idea that they are not always free from oxygen. In this memoir 

 the author shows that they do not owe their fluidity to naphtha. The 

 bitumen of Bechelbronn, which M. Boussingault has principally stu- 

 died, is viscid and of a dark brown colour. From its uses it has been 

 called mineral fat, it being advantageously used instead of organic 

 fatty substances to diminish the friction of machines, &c. Alcohol 

 at 40" acts on bitumen, particularly when heated, and acquires a yel- 

 low tint. Sulphuric aether readily dissolves it. Heated in a retort to 

 2l2°Fahr. nothing distils : this proves that it contains no naphtha. 



By distilling the bituminous sand with water, M. Boussingault has 

 obtained a volatile oily principle, which he calls petrolene, consider- 

 ing it to be the volatile principle of petroleum : it possesses the fol- 

 lowing properties : 



Petrolene is of a pale yellow colour, of a slight taste, and possesses 

 an odour resembling bitumen ; at the temperature of 70° Fahr. its 

 specific gravity is 0-891 j at 18° Fahr. it does not lose its fluidity j it 

 stains paper like the essential oils, burns with much smoke, boils at 

 536° Fahr. ; alcohol dissolves a small quantity of it, but it is much 

 more soluble in aether. It is composed of 

 Carbon, .. SS-f) 

 Hydrogen, . . 115 

 so that it is a carburet of hydrogen isomeric with the essential oils of 



* [That a battery of two hundred and thirty-two pairs of four- and five- 

 inch plates, or even of a hundred pairs, should violently convulse rabbits, 

 eels and/rog.?, is by no means an extraordinary result. The really terrific 

 experiments made hy Dr. Ure on the murderer Clydesdale, at Glasgow, 

 were performed with a voltaic battery consisting of 270 pairs of four-inch 

 plates, charged with dilute nitro-sulphuric acid. — Edit.] 



[ From VImlihd,Scj)t. '2\, 1836. 



