INDEX. 
ADELSBERG STALACTITE GROTTO, 
121. 
Aerial ocean, 53, 73 
Agassiz on " erratic blocks," 127. 
Air, bad, in close rooms, 57. 
carrying water-vapour, 77, 
78, 81, 96. 
elasticity of, 61. 
its pressure on the earth, 64. 
made of two gases, 55. 
rising of hot, 72. 
weight of, 62. 
Air-atoms, forming waves of 
sound, 135. 
Air-bubbles bursting in waves, 
148. 
Air-currents, cause of, 71. 
Albuminoids, 157, 164. 
Almond-seed, 156. 
Alum Bay Chine, 116. 
Ammonia in air, 58. 
Anaxagoras on size of the sun, 29. 
Antarctic Continent, snowfields 
of, 97. 
Anthers of stamens, 168. 
bursting of, 170 
Aqueous vapour, whence it comes, 
80. 
Arbroath, waste of cliffs at, 122. 
Ariel's song, 5. 
Atmosphere causing the spread of 
light, 74. 
height of, 62. 
weight of, 64-70. 
Aurora borealis, 55, 75. 
Avalanche, noise of, 152. 
BALLOON ASCENTS, 62. 
Balls illustrating sound waves, 133. 
Barometer and its action, 67-70. 
Bee-bread, 209. 
Bee, pollen-masses on head of, 
239- 
Bees and flowers useful to each 
other, 242. 
and orchids, 237. 
cementing dead bodies, 217. 
feeding of, 210, 212. 
Huber on, 202. 
length of life of, 217. 
nursing, 206. 
sentinel, 217. 
swarming, 203, 213, 214. 
ventilating, 216. 
visit one set of flowers at a 
time, 221, 231. 
worker, queen, and drone, 
204. 
245 
