932 TRANSACTIONS OF THE AMERICAN INSTITUTE. 



0.93169 at 58° F. A part of the latter treated with steam of 280° 

 F., and carefully washed with boiling water, whereby most of the 

 suspended vegetable impurities are separated, showed at 50° F., 

 the specific weight of 0.93433, This latter approximates very 

 closely that of the linseed oil, which, except in color, is very 

 similar to the cotton seed oil. The latter is a siccative oil, and in 

 many instances is a good substitute for the former. It is readil}' 

 soluble in ether, sulphide of carbon and benzol, but not so in alco- 

 hol, even when heated; however, alcohol dissolves tlwit 'pavt of 

 the substance from vrhich the crude oil derives its color. This 

 color is not produced by the husks, because they do scarcely give 

 any soluljle substance neither to ether, alcohol, sulphide of carbon, 

 nor to water; but it is produced l)y small black flaculre, which are 

 floating in the yellowish white liquid, and are easily recognized 

 by the unassisted eye. Under the microscope they appear tilled 

 with a resinous fatty body of a dark rose color, ^^hich is soluble 

 in alcohol and ether, and (under simultaneous decomposition) in 

 weak solutions of caustic alkalies. If the seed kernels arc pounded 

 in a mortar, they yield a dark reddish-brown liquid. The original 

 matter is originally of a yellowish green color, and may be so 

 extracted by heating with alcohol under an exhausted receiver of 

 an air pump and evaporating in a vacuum. Digestion in the 

 presence of the atmosphere yields the dark color as stated, which 

 is evidently the result of oxydation of the coloring matter of the 

 oil, but neither mordanized cotton nor wooleiican be dyed with it. 

 Treated with re-agents, the crude oil behaves very peculiarly; 

 concentrated oil of vitriol produces a Ijeautiful purple color, which 

 by stirring becomes darker; after 24 hours the mixture is very 

 thick and of a reddish brown tint, sulphurous acid is developed 

 and the color becomes of a dark blood red; after leaving it again 

 for 24 hours, it becomes a solid blackish mass. Adding strong 

 nitric acid, the oil becomes first of a dark olive green, but soon 

 liffht orauire red; after 24 hours it is solid and shows a dark orange 

 red color. By mixing the oil with a solution of potassa of 1.22 

 specific gravity, the licjuid is first yellowish, then, on stirring with 

 a glass rod, those parts in the test tube Avhich are most exposed 

 to the air take a bluish purple color, similar to that of a solution 

 of pyrogallic acid in potassa, when exposed to the air; after 24 

 hours the oil is getting solid; the same result'is obtained by soda 

 lye. By adding stroug liquor of ammonia, a yellowish green 

 color is produced; strong phosphorous acid shaked with the oil 



