330 TRANSACTIONS OF THE 



rock, and tlien from the soil, enters a growing plant and becomes 

 part of it, it has progressed, and in a manner which analysis 

 alone cannot recognize; and when, from the decay of the plant, 

 the primary has again returned to the soil, it is rendered capable 

 of being absorbed by a higher class of plants, which in its turn, 

 by its decay, renders up its primaries fitted for a higher assimila- 

 tion. It is fair to suppose, and indeed is generally admitted, that 

 the first plants grown upon our soil were mere lichens and mosses. 

 They took carbonic acid from the atmosphere, retained the carbon 

 to increase their bulk, and received from the soil the inorganic 

 primaries, which, upon their decay, were returned to the soil, 

 thus fitting it for the growth of higher organisms, which, in their 

 turn, performed similar offices. This is, as we shall show, equally 

 true of animal life. 



The fresh debris of the rock at the mountain side is incapable 

 of producing the higher class of vegetable growth. The double 

 rose cannot be sustained in such a soil, while the single rose taken 

 from a primitive soil and carried to the older soil of the garden y 

 may be gradually improved to the double rose; and simply 

 because the inorganic constituents of the garden soil have been 

 in organic life many times, and have thus been rendered fit 

 pabulum for the new comer. 



Every practical farmer, who has a sufiicient knowledge of 

 chemistry to observe truths as they occur, knows that the sulphate 

 of lime made from bones by treating them with sulphuric acid to 

 render them surperphosphate of lime, is worth many times its 

 weight of native sulphate of lime known as plaster of Paris; and 

 that while the one is suited for the use of a higher class of garden 

 crops, the other is comparatively inefficient. 



Now it is evident that the lime in the bones of the animal was 

 received from its food, which being a higher class of vegetable 

 growth, could assimilate only such lime as had been before many 

 times in organic form, and therefore is rendered capable ef enter- 

 ing the higher class of plants, and of being appropriated instead 

 of being parted with as excretia; for plants do throw off any 

 material held in solution by water, which is not sufiiciently 

 progressed to form part of their structure. The same truth will 

 apply to the phosphate of lime separated from the bone, as com- 



