NEW OLEAGIIfOUS COMPOUXB. S^l 



pal properties ar« its specific levity, the retention of its 

 oleaginous appearance in hot water, and finally its total de- 

 composition in cold water. 



Exper, 4. — The same proportions of benzoic acid and ^^P- 4— NitrU 

 camphor were dissolved in half an ounce of nitric ether : 

 the colour in this combination, however, soon changed to 

 a reddish brown, and a quantity of an oleaginous substance 

 of the same colour was produced, without the admixture of 

 any water. It is probable, I think, that the colour in this 

 combination was produced from the action of the ether on a 

 quantity of resinous matter in the acid. From a subsequent 

 experiment, however^ precisely in the same proportion, 

 there was scarcely any of this compound produced ; but on 

 the addition of half an ounce of water there was a copioui 

 production of it, whicli gravitated to the bottom of tha 

 phial. After standing for several hours, a number of crys- 

 tals had formed within it, and it had become much denser, 

 and resembled in appearance melted phosphorus. Thus we 

 see that water greatly facilitates the formation of the com- 

 pound, and also causes by dilution the subsequent forma- 

 tion of crystals. When these two experiments were re- 

 peated with a purer acid, in the same proportions, analo- 

 gous results^ were produced; but the compounds were of a 

 pale white colour: and thus, I think, proving satisfac- 

 torily, that the colour in the former experiments was ow- 

 ing to the impurity of the acid. The general properties of 

 this compound are its greater specific gravity; its spon* 

 taneous formation without water, and its immediate pro- 

 duction on the admixture of this fluid; together with th« 

 resulting formation of crystals, which I suppose are pro- 

 , duced in the ratio to the power orf dilution. It is acid, 

 ^nd also preserves its oleaginous appearance in either hot 

 "Or cold water, and is partly dissolved. If, however, it be 

 put into too large a quantity of either, it is extremely pro- 

 bable that it will be dissolved or decomposed ; because the 

 power of attraction, which will preserve it in a small 

 jjuantity, will be totally annihilated by a greater. 

 U' Thus after observing the peculiar combinations of benzoic 

 add and caraphor with alcohol and ethers, I was induced 

 • ' farther 



