AMERICAN INSTITUTE. 



35*7 



tlie pliuspliatic rocks and volcanic deposits, miscalled gvmios, altliough. 

 ground and treated with sulphuric acid, have no value as fertilizers^ and 

 cannot lic absorbed into the higher chiss of phmts, such as are now required 

 for the use of men and animals. They must first be taken up by lichens and 

 mosses, and be progressed by them in a way which chemistrj^ as yet has 

 failed to discover, and on their decay and re-deposit of their phosphates in 

 the soil, be absorbed by a higher class of plants for further progression, 

 and so on through nature's laboratory, until we find the progressed phos- 

 phates occupying the bones of animals. 



Man might as well try to exist on dissolved rocks instead of the same 

 constituents composing plaiits in a progressed state, as to attempt to feed 

 plants or primitive phosphates, no matter how manipulated by grinding 

 and acids. We know this experimentally and practically, and this new 

 discovery of the Freuch Academy only serves to endorse our oft-told views 

 to the extent of their investigations. 



ON THE DIFFERENT KINDS OF PHOSPHATES OF LIME. 



Translated from the French by H. Meigs. 



The Academy has charged M. Boussingault and me with the examination 

 of a note of M. Moride, containing observations, and the results of many 

 experiments, on the phosphates of lime employed as manure, and particu- 

 larly on those of the compositions called minerals^ massses of which, more 

 or less considerable, are found hurried in the soil. 



It is not the first time that this important question has called for the 

 investigation of science: a great work, now in a course of publication, of 

 our illustrious permanent secretary, M. Elie de Beaumont, is at this moment 

 drawing the attention of the public to the same subject. 



There would indeed be an iujmense benefit to agriculture in obtaininf^ 

 phosphates of lime, assimilable by plants, to the same extent as phosphate 

 of ground bones acidified, imperfectly carbonized, or mixed with organic 

 azotous substances, such as are present in the refuse of sugar refineries. 



Under these conditions phosphate of lime, by virtue of its interposition 

 in the midst of organic tissue, presents itself in a state of extreme divi- 

 sion easily assailable by acids. 



In England its divisibility, as well as it is dissolubility, are still further 

 increased by treating the bones with sulphuric acid, which forms sulphate 

 and bisulphate of lime, attacking even the organic tissue, so that the 

 ossous fragments become soft and friable. 



In presence of the carbonate limestone of the soil, or of that which is 

 added to the bones thus disintegrated, the excess of acid is found saturated, 

 the organic azotous matter becomes spontaneously changeable, and the 

 rvinmuniacal products of its decomposition cooperate of themselves to the 

 nutrition of plants. ' 



Eifect,s analogous to these take place when we employ carbonized bones 

 in powder, mixed v^ilh the blood used in effecting the clarification of sugar or 

 sirups ; there are added to them reactions equally favorable, dependent on 



