668 PHILOSOPHICAL TRANSACTIONS. [aNNO 1780. 



But it was necessary to determine more exactly the quantity of acid retained 

 by the oil: for this purpose 



Exper. 12. To -i- dr. of pure salt of tartar he added so much of the acid ob- 

 tained in exper. 10, as was sufficient to saturate it completely; 6-I- dr. of the acid 

 were required for this purpose. 



Exper. 13. Now 2 dr. of salt of tartar were found barely sufficient for the 

 complete saturation of the acid contained in the water impregnated with this acid 

 in exper. 1 1. Therefore, calculating according to the results obtained in exper. 

 12, the quantity of acid contained in this water amounted to 3 oz. 2 dr. 



Exper. 14. Three oz. of the reddish-brown oil that had been edulcorated with 

 water, exper. 1 1, were mixed with an equal quantity of distilled water, and placed 

 over a lamp. Before the water rose up, there came over a limpid oil, resembling 

 ethereal oil both in smell and taste ; next along with the water there passed over 

 a portion of white oil. When the whole had distilled over, the lamp was re- 

 moved, and 3 oz. of oil were separated from the water, which had acquired an 

 acid taste. 



Exper. 15. The whole quantity of oil, exper. 11, being distilled per se, by 

 the heat of a lamp, a limpid oil was obtained, similar to that in exper. 14; and a 

 small quantity of red acid remained at the bottom. 



Exper. 16. This oil, exper. 15, being digested with a strong heat, in circu- 

 latory vessels, it acquired a darker colour, till at length it became of a dark, bay.* 



Exper. 17. The residuum after the distillation in exper. 15 was exposed to a 

 strong heat, till nothing more could be distilled from it. On breaking the retort 

 there was found a coally matter, which weighed 3 oz. 18 dr. exactly similar to 

 that obtained in exper. 1, 4, 7, Q.-f- 



Exper. 18, 19. Three dr, of the oil, exper. 14, 15, were mixed with 2 oz. of 

 sp. of wine. Of this mixture ~ was subjected to digestion in circulatory vessels, 

 and the other half was distilled in a retort. The first portion was not dissolved 

 by the sp. of wine, but the latter was. 



Exper. 20. On the addition of water both liquors turned milky; but they 

 afterwards became clear, the oil rising up to the surface. 



Exper. 21, 22. By adding caustic salt of tartar made hot to the rectified oil, 

 exper. 14, boiling hot, a soap was produced. The result was nearly the same 

 with the oil of exper. 1 1 . 



* Dr. C. remarks that on subjecting Dippel's animal oil to tlie same treatment, it underwent a 



similar change. 



t On comparing the results obtained in exper. 10, 13, 17, with each other, it will appear, says 

 Dr. C, that Ibij. of suet consist of pure oil li oz,, acid 7 oz, 2 scr., carbonaceous matter 10 oz. 

 6" dr. 1 scr. 



