496 



INDEX. 



Maclear (T.), meteorological observa- 

 tions at the Cape of Good Hope, 302. 



Macro-micro, account of the, 268. 



Macroura, on the metamorphoses in 

 the, 371. 



Magnet, power of masses of iron to 



control the attractive force of, 69 ; 



improved magnets, 486. 

 Magnetic action, influence of screens 



in arresting, 69; speculations on 



the nature of, 71. 

 experiments in the S. of Europe 



and Asia Minor, 163 ; made on the 



coast of Africa, 130; on board an 



iron steam-vessel, 378. 

 ■ forces, on the, 253. 

 influence of the solar rays, on the, 



175, 176. 

 intensity, terrestrial, 37, 400. 



— phenomena, Arago's, on, 93. 



pole, north, position of the, 254. 



pole, south, on the position of, 323. 



— power of soft iron, 187. 



variation, on, 195. 



Magnetic-electrical machines, on, 412. 

 Magnetic needle, on irregularities in 



the, 123 ; influence of the sun's rays 

 on, 175 ; on the influence they ex- 

 ercise over each other, 282 ; on the 

 dip of, 394 ; on the variation of, 395 ; 

 comparison of observations of the 

 dip and variation of, 396. 



Magnetical observations by Capt. 

 Back, discussion of the, 394, 400. 



Magnetism, apparatus for magnetical 

 observations, 170. 



■ , terrestrial, on the electric ori- 

 gin of the phenomena of, 23 ; pro- 

 bably not essentially distinct from 

 electricity, 25 ; variable intensity of, 

 37 ; influence of the aurora borealis 

 on, 37 ; its influence in eliciting 

 electricity, 96 ; irregularities in the 

 indications of the intensity of, 124; 

 Gauss's memoir, 166 ; on determi- 

 ning the direction and intensity of, 

 1 85 ; geometrical researches in, 320, 

 368 ; Humboldt's plan for the obser- 

 vation of the phenomena of, 418 ; 

 magnetic intensity, 400. 



Magneto-electric induction, 96, 177; 

 intensity in different metals, 1 78. 



Magneto-electric phenomena discover- 

 ed by Faraday, on the law which 

 connects, 159. 



Malcolm (Sir John), notice of the late, 

 224. 



Mammary glands of the Ornithorhyn- 



chus paradoxus, 133. 

 Mars, on the atmosphere of, 71, 158. 

 Marsupial animals, on the generation 



of, 279 ; on the brain in, 460. 

 Mease (Dr.) on the dry-rot of ships, 



482. 



Meckel (Dr.), notice of, 232. 



Medal-ruling, improvement in, 139. 



Mediterranean, new volcano in, 94, 

 107, 184, 196, 284. 



Medulla oblongata and spinalis, on the 

 reflex function of the, 210 ; on the 

 structure of the, 331 ; on the special 

 function of the, 463. 



Men dip Hills, on the caverns of the, 55. 



Mercury, equivalent number for, 197. 



Metallic poisons, electro-chemical me- 

 thod for the detection of, 5. 



Metals, on the dilatation of the, 69. 



Metals and minerals, electrical rela- 

 tions of, 317. 



Metaphosphoric acid, 209. 



Meteor, extraordinary, 159. 



Meteoric iron, remarkable mass of, 

 203, 213. 



Meteorology, deductions from obser- 

 vations made at Port Louis, 477. 



, observations made at the Royal 



Soeietv, on, 42. 



of'Dukhun, 296.; of Cape of 



Good Hope, 302, 363. 



Micrometer, wired, concave achroma- 

 tic lens adapted to, 268. 



Microscopes, solar and oxy -hydrogen 

 gas, 457. 



Mineral springs of the Pyrenees, 382. 



Mirage, caused not so much by eva- 

 poration as by the direct effect of 

 the solar rays, 32. 



Mitscherlich (Prof.), the Royal medal 

 adjudged to, 221. 



Moira brine spring, analysis of, and 

 on the extraction of bromine, 295. 



Molecular attraction, 157. 



Mollusca, marine testaceous, 131. 



, economy of the, 201 ; of the 



power they possess to dissolve shells 

 &c, 202 ; deposition of shelly mat- 

 ter by, 203 ; anomalies observed in 

 the habitations of the, 340. 



Moon, theory of the, 25, 52, 75, 128, 

 253, 270. 



Morgan (W.) 5 notice of the late, 226. 

 Motion, on the cause of, 410. 

 Mountain barometer, description of a, 

 40. 



