il 
show that there was practically no change when the fat was kept 
in the dark :— 
Petroleum Carbon tetra- Alcohol 
spirit. Ether. chloride. 97%. 
Original fat Soluble ... Soluble ... Soluble... Insoluble. 
Exposed in Insoluble ... Insoluble ... Insoluble ..._ Insoluble. 
light 
Exposed in Faintly opal- Faintly opal- Faintly opal- Insoluble. 
dark escent escent escent 
solution solution solution 
Lastly, the effect of heat upon the appearance and properties 
of the fat was observed :— 
A.—3-5712 grammes, exposed to air and light at 100° C. 
Time of exposure Gain per gramme 
in days. Actual gain. er day. 
1 isk 0°1912 gm. ea 0:05352 gm, 
2 iat 0:0614 _,, ee 0:03714 ,, 
3 = 00140 _,, ae 0:00392 _,, 
+ nil. eae oa nil, 
The following is a record of observations made on heating the 
fat slowly from 15° C. to 24 Os 
15° C.- 50° C.—The fat became less granular, finally 
assuming a homogenous appearance, and 
was of a dark brown col 
50° C.-100° C.—No change observed, e 
assumed a redder tint 
100° €.-110° C.—More transparent. 
120° C.-130° C.—Colour still lighter. 
130° C._180° C.—Appearance of small bubbles, probably due 
to the escape of a small quantity of volatile 
olour. 
-cept that the colour 
matter. ; was 
200° C.-240° C.—A greenish-brown mobile liquid. 
ling, the fat remained as a brown, viscous liquid of the 
eer il, and the solubility remained as that of 
ure in thin layers this liquid did not 
orded of the fat. eet a 
film appeared, whereas on further exposure the thinnes 
eins anak ‘ transparent skin of the nature of varnish. | 
