LARD AND LARD ADULTERATIONS. 469 



This method evidently was suggested by the article in Watt's old 

 dictionary (Linseed oil), in which the action of sulphur chloride on flax 

 oil is described (incorrectly, as Mr. Warren has shown). 



The method was tried by Dr. (3. A. Grain pton during the lard inves- 

 tigations on a few of the samples submitted, viz: 



5645. Cotton oil. 



5624. Olive oil. 



5620. Peanut oil. 



5556. Fairbank's lard. 



5626. Tallow steariue. 



5591. Squire's lard. 



5672. Hog's-liead lard. 



On adding the re-agent, mixing thoroughly, and heating on the water- 

 bath the oils became perfectly solid. The lards did not become solid 

 and the stearine was not affected at all. 



5591. A pure standard lard was scarcely attacked by the re-agent. 



5672. Eendered in laboratory from the head fat was more readily 

 affected by the re-agent. 



Mr. Grampton made a preliminary examination of the solid products 

 formed, but came to the conclusion that they contained no sulphur. If it 

 be true that only oleine is attacked by the chloride of sulphur and not 

 palmitiue nor stearine, then pure lard ought to give a partial product 

 insoluble in ether and carbon disulphide. Yet lard so treated is prac- 

 tically soluble in the re-agents named. The vegetable oils appear to be 

 easily attacked by the chloride of sulphur and the action of the re- 

 agent does not seem to wholly depend on the amount of oleine present. 



I think Mr. Warren's method may prove of great value qualitatively 

 and perhaps quantitatively. 



QUANTITATIVE DETERMINATION OF ADULTERANTS IN LARD. 



Many attempts have been made to determine quantitatively the 

 amount of adulterants in lard. These attempts have not been attended 

 with much success. They may be classified as follows : 



(1) By weight of uudissolved residue when the mixed fat is treated 

 with ether. 



(2) By the relative intensity of color produced by sulphuric acid and 

 other re-agents. 



(3) By the relative quantities of silver or gold reduced, or intensity of 

 coloration in Bechi's, Millian's, and Hirschsohn's processes. 



(4) By calculation from specific gravity. 



(5) By calculation from iodine absorption. 

 (G) By calculation from refractive index. 



(7) By determination of the insoluble "matter produced by treatment 

 with chloride of sulphur. 



(8) By rise of temperature with sulphuric acid. 



(9) By calculation from melting point. 



