INDEX. 



485 



CETUS. 



Cetus, nebulous patches crossing, 417. 



Chaldeans, the, mean longitude found 

 from observations of, 36 ; result of 

 comparison of their observations 

 with modern, 38. 



Challis, Professor, Brewster's analysis 

 of light questioned by, 161. 



Charcoal, light produced by electri- 

 city from, 302-303. 



Charles V., the Emperor, observa- 

 tions on comets, made in his reign, 

 370. 



Chaudes Aigues, temperature of, 231. 



Chemical action of rays of the solar 

 spectrum, 203, 207 ; varying maxi- 

 mum of energy, 208 ; action vary- 

 ing with refrangibility, 209-212; 

 action in luminous spectrum not 

 continuous, 213 ; energy an inde- 

 pendent property of rays, 214; 

 properties of the parathermic rays, 

 219 ; action of light maintaining 

 vegetation, 249 ; affinities the source 

 of the power of steam, 278 ; of elec- 

 tricity on oxygen, 284 ; eliciting 

 voltaic electricity, 297, 300 ; vol- 

 taic electricity, an agent in, ana- 

 lysis, 307, 308. 



combinations, theory of, 110; 



invariable proportions of, 111; co- 

 hesive force inducing, 112 ; pro- 

 ducing combustion, 270. 



force, the power of, 112. 



rays, causing the deposition of 



dew, 269. 



Chile, elevation of land by an earth- 

 quake in, 234. 



China, distinct flora of, 251. 



Sea, the, monsoons blowing 



over, 124. 



ink, polarized light reflected 



from, 193. 



Chinese, the, observations of, on the 

 mean motions of Jupiter and 

 Saturn, 25 ; proof of their early 

 study of astronomy, 88 ; decimal 

 divisions used by, 90 ; elements of 

 comets computed from their ob- 

 servation, 365; comet of 1264 

 recorded by, 370. 



: Tartary, herbarium collected in, 

 250, 251. 



COAL. 



Chladtii, discovery of, in musical sci- 

 ence, 145. 



Christian era, traces of astronomical 

 records before, 365. 



Chromatype, the invention of, 206. 



Chronology, dependent on astronomy, 

 87-89. 



Chrysotype, the, coloured photographs 

 obtained from, 206. 



Circuit, galvanic, modes of obtaining, 

 332. 



Circular arcs, principle with regard to 

 their sines and cosines, a pledge for 

 the stability of the solar system, 20. 



motion, ratio of forces procuring, 



382. 



orbits of planets distinguished 



from elliptical, 8 ; of satellites, 27. 



polarization of light, 189-192 ; 



of heat, 266. 



Circumference of the earth, 49. 



Civil time, measure of its periods, 83 ; 

 not precisely adjusted to solar re- 

 volutions, 85. 



Clairaut, periodic time of Halley's 

 comet computed by, 362, 363. 



Cleavages of crystals, 109 ; position 

 of, affecting the intensity of mag- 

 netic action, 350. 



Climates, planetary, 225, 226 ; cause 

 of the different terrestrial, 237 ; 

 phenomena affecting, 239, 240; 

 causes of variety of, 243, 244; 

 milder, of the Polar Ocean, 245, 

 246 ; like mean annual temperatures 

 not ensuring like, 246 ; compensa- 

 tions of irregularities, 247. 



Clocks, showing apparent sidereal 

 time, 83 ; regulated to show de- 

 cimal time, 84 ; irregular action of, 

 corrected by the laws of unequal 

 expansion, 272. 



Clouds, circling the belt of equatorial 

 calms, 123 ; region of, 124 ; elec- 

 tricity evolved from, 291-292. 



Cloyne, Bishop of, his calculation of 

 the moon's mass, 56. 



Coal-measures, tropical plants in, 72, 

 73 ; age of their formation, 75. 



Coal, chemical force evolved from, by 

 combustion, 278 ; source of its 

 combustible qualities, 279, 280. 



