358 



BOARD OF AGRICULTURE. 



Animal Dust. 

 This fertilizer, which of late has been introduced into our 

 markets, is prepared from the blood, the meat scraps and a 

 part of the bones obtained in some of the large slaughtering- 

 houses in Boston and its vicinity. Most prominent at present 

 is the manufacture of animal dust at the great abattoir of the 

 Butchers' Slaughtering and Melting Association, at Brighton. 

 I visited the establishment during the month of October last, 

 and could but admire its neatness and its superior accommo- 

 dations for the work designed. The slaughter-houses are 

 represented to be large enough to take care of three hundred 

 head of cattle and two thousand sheep per day. The daily 

 production of the fertilizer will amount when in full force to 

 six tons. Fifty dollars are charged per ton to farmers. After 

 passing the meat scraps and the smaller and softer bones 

 through the rendering process to secure their fat, the refuse 

 matter is mixed with the blood and dried by steam heat in 

 Hogel's drier. The soup from the boiling of meat and bones 

 containing the soluble saline compounds of both, with a com- 

 paratively small quantity of organic matter, is discharged, not 

 paying thus for the expenses for further treatment. The 

 dried mass, when ground and finished for sale, forms a red- 

 dish gray, coarse powder, of a peculiar, yet not very ofiensive, 

 odor. I have had occasion to test it repeatedly. The follow- 

 ing analytical statement represents my results : — 



Moisture lost at 100° C, 

 Animal matter, 

 Ash constituents, . 

 Nitrogen in animal matter, 

 Phosphoric acid in ash, . 



The rendering of the bones by steam, under considerable 

 pressure, disintegrates them to such an extent that a part of 

 the neutral phosphate of lime is rendered soluble in a concen- 

 trated solution of citrate of ammonia, and is thus in a superior 

 degree ready for assimilation, as compared with ordinary 



