BONE MANURE. 185 



sulphuric acid diluted with three or four parts of 

 water, and after they have been digested for some 

 time, to add one hundred parts of water, and 

 sprinkle this mixture over the field before the 

 plough. In a few seconds, the free acids unite 

 with the bases contained in the earth, and a neutral 

 salt is formed in a very fine state of division. Ex- 

 periments instituted on a soil formed from grau- 

 wacke, for the purpose of ascertaining the action 

 of manure thus prepared, have distinctly shown 

 that neither corn, nor kitchen-garden plants, suffer 

 injurious effects in consequence, but that on the 

 contrary they thrive with much more vigour. 



In the manufactories of glue, many hundred tons 

 of a solution of phosphates in muriatic acid are 

 yearly thrown away as being useless. It would be 

 important to examine whether this solution might 

 not be substituted for the bones. The free acid 

 would combine with the alkalies in the soil, espe- 

 cially with the lime, and a soluble salt would thus 

 be produced, which is known to possess a favour- 

 able action upon the growth of plants. This salt, 

 muriate of lime (or chloride of calcium), is one of 

 those compounds which attracts water from the 

 atmosphere with great avidity, and might supply 

 the place of gypsum in decomposing carbonate of 

 ammonia, with the formation of sal-ammoniac and 

 carbonate of lime. A solution of bones in muriatic 

 acid placed on land in autumn or in winter would, 

 therefore, not only restore a necessary constituent 



