BONES. ^15 



of obtaining a corrosive product. It will suffice, if 

 but a part of the bone is dissolved. 



Nevertheless, the operation above described is one, 

 that, abstractedly considered, and on account of the 

 destructive nature of sulphuric acid, requires great 

 care and attention, and for this reason will not be 

 within the reach of every farmer. It is, therefore, to 

 be desired, that amongst us also, as in England, the 

 preparation might be manufactured on a large scale, 

 in chemical works, where, by the application of heat, 

 a more complete dissolution of the bones may be 

 accomplished. I have no doubt that it would meet 

 with a very favorable reception in Germany, if it 

 were supplied of undoubted quality and at a mod- 

 erate price.* 



* Since the introduction of superphosphate of lime as a manure, 

 Professor James J. Mapes, editor of the " Working Farmer," has in- 

 vented an article which is in great demand, and is sold under the 

 name of "Improved Phosphate of Lime." 



The inventor found, after repeated trials, that Peruvian guano might 

 be materially improved by the carbonate of ammonia being changed 

 to a sulphate, and by increasing the quantities of ammonia, sulphuric 

 acid, and superphosphate of lime. He therefore, in tiiis new article, 

 combines 100 lbs. of bone-dust with 56 lbs. of sulphuric acid, 36 lbs. of 

 Peruvian guano, and 20 lbs. of sulphate of ammonia. 



This compound, owing to the excess of sulphuric acid, contains no 

 free carbonate of ammonia. Indeed, all the volatile salts, being 

 changed into sulphates, are no longer volatile; they will therefore last 

 in the soil until used up by plants. Unlike guano, it does not injure 

 the roots of plants by immediate contact, and being slowly soluble, it 

 is supplied as rapidly as required by them. 



Many hundred tons of this material have been sold during the past 



