INDEX. 
251 
Spores in coal, 181, 183. 
Sprengel on insects and flowers, 
227, 233, 241. 
Springs, 97. 
mineral, 99. 
Stalactites, 120. 
Stalagmites, 121. 
Stamens of a flower, 168. 
Starch in plants, 157, 162. 
Stars, light of the, 36. 
twinkling of, 75. 
Stigma of a flower, 169. 
Stigmas of orchids, 238. 
Stigmaria root, 178. 
Stomates in leaves, 165. 
Striae made by ice, i"26, 127. 
Sugar, carbon in, 163. 
candy crystals, 89. 
Sun, distance of the, 29. 
size of the, 29. 
heat and light of, 32. 
Sunbeams, 27, 42. 
causing colour, 44. 
causing wind, 71. 
how few reach the earth, 32. 
made of many colours, 40. 
rate at which they travel, 38. 
turning water to vapour, 77, 
80. 
Sunrise, 27. 
Sussex, iron worked in, 197. 
Swamp, Great Dismal, 187. 
Swarming of bees, 203, 213. 
Switzerland, glaciers of, 124. 
TAR FROM COAL, IQI. 
Tennyson's " In Memoriam ' 
cited, 199. 
poem of a flower, 155. 
Thames, drainage of, in. 
mud-banks, 119. 
Thunder, noise of, 151. 
Trade-winds, 73. 
Treacle and water mixing through 
a membrane, 160. 
Trees of the coal-forest, 183. 
Trefoil, structure of flower of, 
235- 
Tumbler of water inverted, 66. 
Tuning-forks vibrating, 146. 
Turin, moraines near, 125. 
Twinkling of stars, 75. 
Tympanum of the ear, 142. 
Tyndall, Dr., cited, 78, 91, 95, 
133, 149- 
UNDERCLAYS of coal, 179. 
Undercliff, Isle of Wight, no. 
Undulatory theory of light, 33-35. 
VIBRATION OF TUNING-FORKS, 
146. 
Violet, structure of the, 234. 
WALES, rain in, 84. 
Water, cutting power of, ni-n8. 
"hard," 99. 
heat required to vaporize, 96. 
how it rises in a plant, 160. 
in U tube kept up by pres- 
sure, 67.- 
solid matter dissolved in, 
112. 
W T ater-dust, 78. 
Waterfalls, how formed, 114. 
Water-flowers in ice, 95. 
W 7 ater-pipes, cause of bursting of, 
95- 
