470 COMPOUND PRODUCTS. CHAP. I. 



far the most abundant. It is generally combined 

 with a portion of phosphoric, carbonic, or sul- 

 phuric acid, forming phosphates, or carbonates, 

 or sulphates of lime. 



Found in- The phosphate of lime is, next to the alkaline 

 * salts, the most abundant ingredient in the ashes of 

 green herbaceous plants whose parts are all in a state 

 of vegetation.* The leaf of a tree bursting from 

 the bud contains in its ashes a greater proportion of 

 earthy phosphate than at any other period : 100 

 parts of the ashes of the leaves of the Oak gathered 

 in May furnished 24 parts of earthy phosphate ; in 

 September, only 18*25. In annual plants the pro- 

 portion of earthy phosphate diminishes from the 

 period of their germination to that of their flower- 

 ing. Plants of the Bean, before flowering, gave 

 14*5 parts of earthy phosphate ; in flower, only 13*5. 

 Carbonate of lime is, next to phosphate of lime, 

 the most abundant of the earthy salts that are found 

 in vegetables. But if the leaves of plants are 

 washed in water the proportion of carbonate is aug- 

 mented. This is owing to the substraction of their 

 alkaline salts and phosphates in a greater propor- 

 tion than their lime. In green herbaceous plants 

 whose parts are in a state of increase, there is but 

 little carbonate of lime ; but the ashes of the bark 

 of trees contain an enormous quantity of carbonate of 

 lime, and much more than the alburnum, as do also 

 the ashes of the wood. The ashes of most seeds 

 * Saussure sur la Vegetation* 



7 



