166 Dr. T. Anderson on certain Products of Decomposition 



excessive violence. I have generally operated on quantities 

 of three pounds, each of which requires a complete day for 

 its distillation, during vv^hich time the operator must never 

 leave it, but constantly attend to the regulation of the heat, 

 and the gradual addition of sulphur in small quantities. When 

 a quantity equal to about half the oil employed has distilled 

 over, the remaining mass becomes excessively viscid ; and just 

 at this point the balloon frequently cracks, the contents escape, 

 and the whole catches fire, and blazes off with a bright yel- 

 low flame and smell of sulphurous acid. 



The product of this distillation, which exactly resembled 

 that of the pure oleic acid, was rectified, and the crystals which 

 deposited from the latter portions were expressed and purified , 

 by successive crystallizations in alcohol. They then presented 

 all the characters of margaric acid, and gave the following 

 results of analysis : — 



{5*275 grains of the acid gave 

 14-*558 ... carbonic acid, and 

 5-919 ... water. 



r 6*358 grains of the acid gave 

 II. -< 17*578 ... carbonic acid, and 

 L 7*212 ... water. 



Which gives the following results per cent.: — 



100-00 100-00 100-00 3325-0 



These results agree completely with the formula for margaric 

 acid, and were further confirmed by the analysis of its silver 

 salt and aether. 



4*643 grains of the silver salt gave 1*325 of silver =28*53 

 per cent. 



7*926 grains of the silver salt gave 2*284 of silver =28*70 

 per cent. 



The calculated result for margarate of silver gives 28*65 

 per cent. 



The aether was prej:>ared in the usual manner, by dissolving 

 the acid in absolute alcohol, and passing dry hydrochloric 

 acid gas through the solution. The product, which possessed 

 all the properties of margaric (ether, gave the following re- 

 isults of analysis: — 



