INDEX. 
K 
Kater, Capt. H., F. R. S., his description of a floating collimator, 
147- 178. 
Kidd, J., M. D. F. R. S., on the anatomy of the mole cricket, 
L 
Life contingencies. Mr. Gompertz on a new mode of determining 
their value, 513. 
Light, artificial, measured by Dr. Ritchie’s photometer, 144. 
M 
Magnetic effect, temporary, induced in iron by rotation, 117 — 
cause of, 323 — law of, 325. 
, permanent, arising from rotation, 347 — general 
description of its phEenomena, 354 — experiments to obtain mea- 
sures of, 358 — mathematical theory of, 393 — compared with 
experiment, 399 — degree of its permanence, 405 — comparative 
effects of slow and rapid rotation, 413. 
needle, general equations for the equilibrium of, 6. 
• susceptibilities, means of magnifying small ones, 482^ — 
distinguished from retentive powers, 
Magnetism, earth’s, of the induced kind, 326 — perhaps induced by 
the sun, 411 — how it may be conveniently neutralized in mag- 
netic experiments, 476. 
, effects of temperature on its intensity, 1. Intensity. 
— of soft iron increased by increase of temperature, 03 — of a 
magnet diminished, 63. 
of various substances manifested during rotation, Messrs. 
Babbage and Herschel on, 467-496 — means of measuring its 
intensity, 472-475— effect of solution of continuity in metals, 481 
— of solders in re-establishing it, 482 — attempt to explain these 
phaenomena, 486. 
. Mr. Christie on the same subject, 497 — experiments 
with various combinations of copper discs and magnets, 497-499 
■ — to determine the variation of rotatory force with the distance, 
502. 507 — with the weights of the discs used, 508, 9. 
Man, Isle of, remains of the Irish elk discovered in, 435. 
Marl, incumbent on peat, remains of the fossil elk occurring in, 431 
— list of fossil shells in, ib. 
Meridian mark, the telescope of a collimator used for that purpose, 
178 — first applied by Mr. Rittenhouse ib. 
