INDEX*. 



315 



regetabl* De 



Clothing, how makes us warm, 147 



use of, 148 



Clouds and fog, difference between, 80 

 Clouds, cause of their various shapes 



appearances, 86 

 color of, 85 



distance, above the earth, 84 

 size of, 84 



sunset, why colored, 86 

 what are, 83 

 when high and low, 83 

 ffoai, anthracite, 225 

 bituminous, 225 

 deposits, extent of, 227 

 mineral, origin of, 225 



produced from v 



matter, 225 

 Cohesive attraction, 11 



illustrations of, 12 

 Cold, greatest artificial, 134 

 natural, 134 



how occasioned by wet clothes, 197 

 what is, 130 

 Color, does not exist in the dark, 270 



influence of, on the deposition of 



dew, 168 



Colors, artificial, why fade in the sun, 271 

 dark, optical effects of, upon the 



size of the figure, 273 

 iSght, effect of, 274 

 disadvantages of a dress of uniform, 



most conspicuous in battle, 274 

 peculiar to arctic regions, 272 

 seven primary, 255 

 warmest for dresses, 175 

 Columns, why larger at the bottom than 



at the top, 42 



Combustion, a process of oxidation, 220 

 chemical action of, 221 

 essential requisites of, 221 

 spontaneous, illustrations of. 



230 



what is, 220 

 Compass, does not always point north and 



south, 297 

 mariner's, 279 



how constructed, 297 

 when discovered, 297 

 Compasses, ships', how affected by light- 

 ning, 299 



Compressibility, 6 

 Concord il -discord, what arc, 120 

 Contagion, susceptibility to, 810 



what is, 811 



Convection of h-eat, 153 

 Copper, poisonous effects of, 310 

 Cornea, effect of flattening, 265 



of the eye, 263 

 Cornic<s, what is a, 47, 48 

 Corrosive-sublimate, what ts> 810 

 Coughing, what is, 122 

 Countries, least cloudy, 10S 

 most cloudy, 107 

 some, why destitute of rain, 



110 



Cowl, use of, upon a chimney, 216 

 Cream-, why rises upon milk, 64 



Crying, what Is, 123 



Cultivation, how increases the "warmth of 



a country, 198 

 and Curtain, behind a pulpit, influence of on 



sound, 126 

 Cylinder, strength of -a, 36 



Dead body, whycold,238 



Decay ift substances, how occasioned and 



promoted, 806 

 Density, what is, 6 

 Diseases, when contagious, 811 

 Dew and rain, difference between, 163 

 Dew, cause of, 164 



deposited most readily on cleat 



nights, 163 

 does not fall, 168 

 does not form on exposed parts (# 



the human body, reason of, 170 

 falls abundantly on cultivated soils, 



none on a windy night, 164 

 none on cloudy nights, 163 

 phenomenon of, 162 

 rarely observed in cities, 168 

 when converted into frost, 163 

 when most copious, 166 

 why more abundant 0*1 some sub- 

 stances than others, 164 

 why rolls in drops on fcavcs, 169 

 Dewdrop, why round, 168 . 

 Diamond, cause of its brilliancy, 256 

 Disinfecting agents, 307 

 Distillation, how effected, 196 



what is, 195 

 Divisibility of matter, 5 

 Doors, why shrink in dry weather, 199 

 swell in damp weather, 199 

 Dovetailing, what is, 44 

 Draining lands, promotes warmth, 198 

 Draught of air, occasion of, 214 

 a chimney, 214 



stove, 214 



v/hcn there is none, 215 

 Dress, arrangement of colors in, 272, 273 

 Presses, white^" why adapted for summer, 



Drum, why sounds, 121 



Drying and distilling, difference between^ 



1$6 

 Ducks, why not made wet with water, 



169 



Ductility, 11 

 Dust, how expelled from a crtat or carpet 



by beating, 26 

 Dunghill, cause of the heat t>f, 229 



Car, construction of, 115 



drum of, 114 

 Sarthen vessels, why crack in cold we* 



thcr, 180 

 Earth, heat of, 136 



