QUESTIONS. 279 



ble article in the food of plants ? What does it do ? Of what are the 

 solid parts of plants formed ? 20G. Describe ammonia. What is it ? 

 How essential is it to plants ? 207. Atmospheric food of plants ? The 

 four essential elements ? 208. Is it possible for plants to grow without 

 any connection with the earth ? 209. Is the C in plants pure ? Char 

 ring ? What is done by charring ? 210. Peat ? Anthracite and bitu 

 minous coal ? What may be seen in them? 211. What happens in 

 charring ? What is consumed ? What happens when charcoal is 

 burnt in air ? 212. Combustion ? The combustible or atmospheric 

 elements ? The incombustible or mineral elements ? How many aro 

 found in the ashes of every plant ? The ashes of plants of particular 

 families remarkable for ? 213. The ashes of plants of the Cruciferous 

 Family contain ? Cruciferous Family ? 214. The ashes of plants of 

 the Pulse Family ? Sulphate of lime ? Lime ? 215. What is found in 

 the ashes of wheat and other grain ? Phosphate of lime ? Phosphoric 

 acid ? Phosphorus ? What tendency has it to combine with O ? What 

 use is made of it ? Why is phosphate of lime called bone earth ? 216. 

 In what plants is silica found ? What properties does it give ? Silica ? 

 Describe it. Why is it considered an acid ? [See, also, art. 270. J 

 217. Where is potash found ? How is it obtained ? Soft soap formed ? 

 Pearlash ? 218. Common potash ? Potassa ? Potassium r 219. Soda ? 

 Where is it found ? Sodium ? 220. For what have the ashes of sea- 

 plants been valued ? Whence comes the name alkali ? The alkalies ? 

 Their properties ? 221. How are they acted on by acids ? Give an 

 example. Why is the salt formed called a neutral salt ? In what state 

 do most mineral substances enter plants ? 222. Some plants growing 

 near them contain ? Common salt ? Chlorine ? Very remarkable ? 

 224. What other oxides are found in the ashes of plants ? 225. Mag 

 nesia ? 226. The ashes of plants growing in the sea or on the sea 

 shore contain ? 227. Iodine ? Why is it used in the processes of the 

 daguerreotype ? 228. In what state does iodine occur ? 229. Bromine ? 

 230. What other metals are found in plants ? 231. The acids most 

 important in the structure of plants ? What other acid is essential to 

 some plants ? 233. Are these the only acids found in plants ? Malic- 

 acid ? Citric acid ? Oxalic acid ? Tartaric acid ? 234. In what form 

 are they found in plants ? Potash plants ? Why are they so called ? 

 235. Silica plants ? Why so called ? Lime plants ? Why ? 236. 

 What phosphates are found in all plants ? In what particularly ? What 

 is a phosphate ? 237. Why are the atmospheric elements so called ? 

 Why the earthy ? 238. What else are found in plants ? Fluorine ? 

 Fluoride of calcium ? Mineral food of plants ? 



