‘ixxvi Historical Sketch of the Physical Sciences, 1818. 
slightly soft, and of the size of anut. Boiling alcohol dissolved 
only a portion of it. On cooling, the alcohol let fall a white 
matter in plates, and of a fine pearly lustre. This substance did 
not stain paper like tallow. It melted at the temperature of 276°, 
and on cooling crystallized in brilliant plates. When digested in 
caustic alkalies, it underwent no alteration. Hence it is the 
substance found in human biliary calculi to which Chevreul has 
given the name of cholesterine. 
The portion of the concretion insoluble in alcohol was com-~- 
posed of albumen and phosphate of lime. 
(6.) Concretions from the Lungs of a Cow labouring under 
Phthisis Pulmonalis.—They had the form of small white grains, 
very hard, and united together by a mucous membrane. Weak 
nitric acid dissolved them with a slight effervescence. Ammonia 
threw down a copious precipitate from the solution, and oxalate 
of ammonia occasioned a slight precipitate. Hence the concre- 
tions consisted of phosphate of lime mixed with a little carbonate. 
(7.) Concretions found in a Cavity in the Mesentery of a Bull 
atiacked with Phihisis.—Their composition was precisely the 
same as that of the preceding. 
(8.) Matter found in a Schirrus situated in the Meso-colon of a 
Mare.—This substance was yellowish, greasy to the feel, had 
the odour of rancid oil, and stained strongly blotting paper. It 
was a mixture of albumen and a peculiar matter, consisting 
partly of cholesterine, and partly of a white substance, crystalliz- 
mg in needles, and reddening vegetable blues. When calcined, 
the concretion yielded phosphate and carbonate of lime.—(Ann. 
de Chim. et Phys. ix. 324.) : 
8. Sulphate of Zinc devoured by Spiders.—For the knowledge 
of this fact, one of the most curious yet observed, as connected 
with the food of the insect tribes, we are indebted to the sagacity 
of Mr. Holt. A quantity of sulphate of zinc, which he kept ina 
paper, disappeared, except a small external crust, in the centre of 
which was a large spider. To determine whether this insect, of 
the species called aranea@ scenica, had devoured the salt, he was 
put in a box with fresh sulphate of zinc, which he devoured in the 
same manner, converting it into a yellowish-brown powder. This 
matter was found lighter than the sulphate of zinc, from which it 
had been formed by the spider. It was insoluble in water, and 
LS catie to have been deprived of a portion of its acid,—(See 
nnals of Philosophy, xii. 454.) 
II. MINERALOGY. 
- This branch of natural history is divided into two departments ; 
namely, oryctognosy, and geognosy, or geology. The second of 
these has become of late years a fashionable study in Great 
Britain and America; and numerous essays, containing geolos 
gical descriptions of different tracts of country, more or less 
