INDEX. 
C 
Caoutchouc, the fluid from compressed oil gas an excellent solvent 
of, 465. 
Carbon, Mr. Faraday’s account of new compounds of, and hydro- 
gen, 440. 
, metalloidal, its magnetism, 475. 
Carbonates, earthy, deposited by sea water on overprotected cop- 
per, 330, 336. 
Christie, S. H. Esq. M. A. on the effects of temperature on the 
intensity of magnetic forces, and on the diurnal variation of 
terrestrial magnetic intensity, 1. 
, on the magnetism of iron arising from its rotation, 
347—417. 
— , on the magnetism developed in copper and other 
substances during rotation, 497. 
Collimator, floating, Capt. Rater’s description of one, 147 — 
experiments with various forms of, 156-168 — manner of using, 
170 — vertical, description of, 171. 
Contingencies, Life, new mode of determining their present value, 
513. 
Copper sheathing of ships, mechanical wear of in passing through 
the sea, 332. 
preservation of by iron and other metals, 328. 
, magnetism of, manifested in rotation, 467, 470, 497, &c. 
Cotton, old, how distinguishable from linen, 274. 
Croonian Lecture, on the existence of nerves in the placenta, 66. 
Cricket, mole. See Gryllotalpa. 
Crystals, Mr. Whewell’s general theory of the calculation of their 
angles, and the laws of decrement of their planes, 87-130. 
Crystallography, application of mathematical analysis to the reso- 
lution of its principal problems, 89 — general notation for ex- 
pressing all possible faces and laws of decrement, 90 — corres- 
pondence of this notation with FIauys, 93 — theory of the 
rhomboid, tetrahedron, &c. and their derivatives. See Rhom- 
boid, See. 
D 
Davy, Sir H. Bart. P. R. S., his further researches on the preserva- 
tion of metals by electro-chemical means, 328. 
Deception, optical. Dr. Roget’s explanation of a curious one, 131. 
Deviation due to rotation of a magnetic needle, what, 359 — laws 
of, 379, 381. 
, absolute, id. 
