C. T. JACKSON'S ADDRESS. 453 



" It is doubtful," says Mr. Mason, " if the cultivator ever 

 suspected that he carried to his baru two casks of potash, two 

 casks of lime, one cask of soda, a carboy of oil of vitriol, a 

 large demijohn of phosphoric acid, and a variety of other mat- 

 ters contained in his fourteen tons of fodder, which were as 

 certainly stowed away in his mows, as if conveyed thither in 

 casks and carboys.* " 



Since all plants, from the majestic oak to the most humble 

 herb, contain and require for their existence, the elements of 

 the soil above pointed out, and the cereal grains, especially, 

 abound in phosphates, we cannot fail to perceive that it is ne- 

 cessary that we should make provision for restoring to the soil, 

 in some form or other, those important elements which are re- 

 moved by the crops, and which, like thq phosphates, exist in 

 the soil quite sparingly. 



From what I have already said respecting the use of phos- 

 phate of lime, and of other phosphates derived from it by de- 

 composition in the circulation of plants, you will perceive that 

 it is regarded as one of the most important ingredients of the soil, 

 and that it ought to be supplied by manures which we spread 

 on the land. 



The basis of the bones of all animals is phosphate of lime, 

 and it is derived by animals from their food, the plants draw- 

 ing it from the soil. 



Ground bones or bone dust, is a valuable manure, but is slow 

 in its action. If we wish to hasten its absorption by plants, it 

 is necessary to decompose it by means of sulphuric acid, adding 

 thirty pounds of common oil of vitriol to one hundred pounds 

 of bones, and then drying up the pasty mass by mixing it with 

 leached ashes and soil, so as to convert the whole into a dry 

 powder, capable of being strewn upon the soil broadcast. The 

 ashes act chemically as well as mechanically upon this mixture, 

 phosphates of the alkalies resulting from decomposition of the 

 silicates of potash and soda. I have mentioned leached ashes, 

 because it is the cheapest, and will answer the purpose, but un- 



* Unpublished lecture delivered before the Providence Franklin Society, by Mr. Owen 

 Mason. 



