4S1 



lode, a new substance which becomes 

 a violet-coloured gas by heat, i. 483. 



lodic acid, ii. 20. 



Iodine : experiments on, i. 507 ; on 

 its occurrence in the mineral springs 

 of South Britain, ii. 402. 



Iodine and oxygen, experiments on a 

 solid compound of, ii. J 9. 



Iron : arseniate of, from Cornwall, 

 i. 43 ; analysis of, i. 45 ; native, i. 

 75, 109. ii. 43, 45; new species of 

 oxide of, i. 126; sulphurets of, i. 

 155 ; magnetic attraction of oxides of, 

 i. 204 ; experiments on the strength 

 of, ii. 87 ; on the separation of from 

 other metals, ii. 148 ; on the ano- 

 malous magnetic action of hot iron 

 between the white and blood-red 

 heat, ii. 164 ; developement of mag- 

 netical properties in, by percussion, 

 ii. 168, 210; on the magnetism of, 

 during rotation, ii. 241, 243, 249, 

 251. 



Ironstone, carbonate of lime, and bitter 

 spar, on the primitive crystals of, 

 i. 422. 



Ivory (J.) on the attractions of homo- 

 geneous ellipsoids, i. 341 ; on La- 

 place's method for computing the 

 attractions of spheroids, i. 413; on 

 the attractions of spheroids, i. 415; 

 new method of deducing a first ap- 

 proximation to the orbit of a comet 

 from three geocentric observations, 

 i. 489 ; on the expansion in a series of 

 the attraction of a spheroid, ii. 162; 

 on the astronomical refractions, ii. 

 200 ; on the figure requisite to main- 

 tain the equilibrium of a homogene- 

 ous fluid mass that revolves upon an 

 axis, ii. 206. 



J. 



Jacob (Dr. A.), account of a membrane 

 in the eye now first described, ii. 116. 



James's powder, method of preparing, 

 i. 57. 



Java swallow, on the glands that se- 

 crete the mucus of which their nests 

 are composed, ii. 77. 



Jenner (Dr. E.) on the migration of 

 birds, ii. 201. 



Johnson (Dr. J. R.) on the Hirudo 

 vulgaris, ii. 54 ; on the genus Pla- 

 naria, ii. 177, 238. 



Johnson (Dr.) on the Hirudo compla- 

 nata and H. stagnalis, now formed 

 into a distinct genus, ii. 78. 



Jones (T.), description of an improved 

 hygrometer, ii. 258. 



Juno, nature and magnitude of, i. 170. 



Jupiter, eclipses of the satellites of, i. 

 312. 



Kater (Capt. H.) on the light of the 

 Cassegrainian telescope compared 

 with that of the Gregorian, i. 468, 

 493 ; method of dividing astronomi- 

 cal circles and other instruments, 

 i. 504 ; experiments for determining 

 the length of the pendulum vibrating 

 seconds in the latitude of London, ii. 

 83; on the length of the French me- 

 tre estimated in parts of the English 

 standard, ii. 8.5 ; experiments for de- 

 termining the variation in the length 

 of the pendulum vibrating seconds, 

 ii. 117; comparison of various British 

 standards of linear measure, ii. 139; 

 remeasurementof the cube, cylinder, 

 and sphere used by the late Sir G. S. 

 Evelyn, ii. 1 50 ; on the best kind of 

 steel and form for a compass needle, 

 ii. 141 ; notice respecting a volcanic 

 appearance in the moon, ii. 142 ; 

 description of a floating collimator, 

 ii. 232 ; account of the construction 

 and adjustment of the new standards 

 of weights and measures, ii. 254 ; 

 description of a vertical floating col- 

 limator, ii. 340 ; on the error in 

 standards of linear measure, ii. 409. 



Kidd (Dr. J.) on the natural produc- 

 tion of saltpetre on the walls of build- 

 ings, i. 509; on naphthaline, ii. 146; 

 anatomy of the mole-cricket, ii. 236. 



Kirkdale, fossil teeth and bones found 

 in a cave at, ii. 165. 



Knight (Thos.) on the penetration of a 

 hemisphere by any number of equal 

 and similar cylinders, i. 434 ; new 

 demonstration of the binomial theo- 

 rem, ii. 52, 70 ; of the attraction of 

 such solids as are terminated by 

 planes, and of solids of greatest at- 

 traction, i. 433 ; on the expansion 

 of functions of multinomials, i. 390; 

 on the construction of logarithmic 

 tables, ii. 69 ; two general proposi- 



