On ihePotatoe Spirit Oil of the French Chemists. 87 



merited, and its boiling point lowered. It is immiscible with 

 water, but nevertheless when agitated with this liquid, it ab- 

 sorbs an appreciable quantity of it. It has a pungent and pe- 

 culiar odour, and a sharp biting taste, somewhat similar to 

 that of the oil of cloves. When gently heated it readily takes 

 fire upon approaching to it a lighted taper, and burns with 

 a clear flame unaccompanied by smoke. It is an excellent 

 solvent for the fats, and also for resinous substances. Cam- 

 phor, for example, is readily dissolved by it; and the same 

 may be said even of copal, if a gentle heat be applied. Potash 

 is taken up by it in considerable quantity, oil of vitriol gives 

 it a crimson colour. To determine its composition the follow- 

 ing experiments were made : 



(I.) 4*24 grains of the oil burned in the usual manner with 

 oxide of copper gave of water 5-06 grains, and of carbonic 

 acid 10*42 grains. 



(2.) 7*71 grains gave of water 9*22 grains, and of carbonic 

 acid 19- 12 grains. 



(3.) 6*63 grains gave of water 8*05 grains, and of carbonic 

 acid 16*26 grains. 



The following are the results deducible from these experi- 

 ments: (1.) (2). (3.) 



Carbon 67*96 68-59 67'84 



Hydrogen.... 13-25 13-28 13-48 



Oxygen 18*79 18-13 18*68 



100 100 100 



The means of the numbers yielded by the three experi- 

 ments are given underneath in column (a.). The numbers in 

 column (b.) are the quotients of the corresponding ones in 

 (a.) divided by the respective atomic weights of carbon, hy- 

 drogen, and oxygen, and those in column (c.) are others in 

 the same ratio with the quotients. 



(a.) (b.) (c.) 



Carbon 68-13 11-132 4*804 



Hydrogen ... 13-33 13-330 5'753 



Oxygen 18-54- 2-317 1-00 



100- 



The inspection of the latter shows that the most probable 

 formula for the oil is C 5 H 6 O l , which would give the follow- 

 ing parts per cent. 



Carbon 68*60 



Hydrogen 13-45 



Oxygen 17*95 



100. 



