vi 



CONTENTS. 



CHAPTER II. 



PAGE 



Soils considered with reference to Horticulture . . .45 

 Sect. 1.— Origin and Kinds of Soils . . . .46 



153. Sandy soil. 155. Clayey soil. 156. Lime. 157. Magnesia. 

 158. Iron, 159. Alluvial soils. 160. Peat. 161. Organic matter. 

 162. Loose naked sands or gravels. 163. Calcareous soils or gravels. 

 164. Loams. 165. Loams are the best soils. 166. Texture. 167. 

 Subsoils. 168. The surface of soils. 169. The plants which grow on 

 a soil. 



Sect. II. — The Improvement of Soils, with a view to Horticulture . 51 

 171. Draining. 172. Altering the texture and composition of soil. 

 173. Changing the inclination of the surface of soils. 174. Burning of 

 soils. 175. Pulverising soils. 177. Rotation of crops. 



CHAPTER III. 



Manures considered with reference to Horticulture . . 56 



Sect. I. — Organic Manures . . . . .56 



181. Fresh and tender vegetables. 182. Spent tanner's bark. 183. 

 Peat soil. 184. Principal vegetable manurec. 185, Animal manures. 

 186. Excrementitious manures. 189, Bones. 190. Vegeto-animai 

 manures. 



Sect. II. — Inorganic Manures . . . .60 



194. Lime. 195. Mild-lime. 197. Carbonate of lime, or chalk. 

 198. Marl. 199. Gypsum. 200. Sea shells. 201. The rationale of 

 the action of lime. 202. The most important uses of lime. 203. Lime 

 compost. 204. Saltpetre. 205. Common salt. 



Sect. III. — Mixed Manures . . . . .64 



207. Coal ashes. 208. Vegetable ashes. 209. Soot. 210. Street 

 manure. 21 1. Composts. 212. Mixed manure in a liquid state. 213. 

 Application of manures. 



CHAPTER IV. 



The Atmosphere considered with reference to Horticulture . 67 



Sect. I. — Heat, considered with reference to Horticulture . . 67 

 219. Conduction of heat. 220. Radiation. 223. Dew, or hoar-frost. 

 224. Dew is never formed upon metals. 225. The formation of dew. 

 226. The effects of radiation. 227. Refrigeration. 228. Protecting 

 plants. 229. The secondary effect which radiation has upon the climate. 



230. The influence of hills upon the nightly temperature of the valleys. 



231. Exalting the powers of the climate. 232. Houses for growing the 

 plants of warm climates. 234. Increasing the heat of the atmosphere 

 and the soil, 235. Frost. 236. Straw mats, bast mats, cloth, wool, or 

 wood. 237. Wall trees. 238. Tender shrubs and trees. 239. A 

 stream or river. 240. Watering. 241. Conclusions. 



Sect. II. — Atmospheric Moisture, considered with reference to Horti- 



cultu7'e ......... 76 



242. Existence of water in air. 243. Hygrometers. 244. Their utility. 

 245. Evaporation. 249. Vapour. 250. Rain. 251. Moisture of the 

 free atmosphere. 252. Artificial climates unnaturally dry. 253. Drain 

 of moisture. 255, Dryness of the atmosphere of hothouses, 256. 

 Coolers of wet porous earthenware. 257, Plants in living rooms. 



