230 Messrs. Dorée and Gardner. Origin and  [Feb. 10, 
ethyl acetate, but insoluble, or difficultly soluble, in petrol. This substance 
began to soften and sinter at 120° and melted sharply at 134°C. This was 
not cholesterol and was probably a phytosterol contained in the meal. The 
mother liquors yielded no further crops of crystalline matter, and dried to a 
viscid oil, which, on standing, showed no sign of erystallising. The yield of 
cholesterol was therefore about half a gramme or 0:023 gramme per day. 
(b) Cooked Beef and Mutton.—After the conclusion of the last experiment 
the dog was fed for a week or more on mixed diet, and given regular exercise, 
' and appeared to be in good condition. It was then fed for 20 days on cooked 
beef and mutton with an occasional bone. The meat was fairly lean, but the 
fat was not specially taken out. The total weight consumed during the 20 days 
was 7470 grammes, or 373°5 grammes per day ; 413 grammes of undried feces 
were passed during this period, and, after treatment, yielded 2:1 grammes of 
unsaponifiable matter in the form of an oily solid. This was dissolved in 
alcohol, partially decolorised with charcoal, and fractionally crystallised ; 
0°615 gramme of crude cholesterol was obtained. It was moderately pure, 
and, after recrystallisation from 85-per-cent. alcohol, melted at 135° to 138°. 
It gave a satisfactory yield of benzoate which melted rather high, 1475, to a 
turbid liquid which cleared at 160°, and, on cooling, showed the colour changes 
in a well-marked manner. The mother lquors deposited about 1 gramme of 
a brown sticky solid which would not crystallise. It was treated in pyridine 
solution with benzoyl chloride, but gave no trace of cholesterol benzoate. 
The yield of cholesterol was therefore about 0°615 gramme, or 0°037 gramme 
per day. 
(c) Sheep’s Bravn.—Atter the last experiment the dog was kept on mixed 
diet and allowed regular exercise for one month, when it was in excellent 
health. It was now given a diet rich in fatty matter and cholesterol—raw 
sheep’s brain—which was continued for 14 days. During this period the 
dog consumed 28 sets of brains, weighing in all 2129 grammes, and appeared 
to relish the food. It was also allowed 170 grammes of bone; 316 grammes 
of undried faeces were passed. The unsaponifiable matter was obtained as 
a buttery mass, weighing about 30 grammes. This, however, was not dry. 
On crystallisation from alcohol, three fractions were obtained, weighing 
respectively 9°8, 5°3, and 1:2 grammes. These were only slightly coloured 
and under the microscope appeared to consist entirely of long pointed needles : 
no typical cholesterol crystals could be seen. Each fraction, after 
recrystallising once from alcohol, appeared pure, and melted at about 96° C. 
On a careful fractional crystallisation no trace of higher melting bodies could 
be obtained. This coprosterol was saturated to bromine. The acetate melted 
at 88° to 89°, and the benzoate at 122° to 123° to clear liquids showing no 
