BONES. 223 



ticularly when, as, unfortunately, still frequently oc- 

 curs, the bone-dust consists principally of coarse 

 pieces. The additions contained in this article, as it 

 is to be procured in the market, are composed mainly 

 of lime. This substance is usually intermixed dur- 

 ing the comminution of the bones, especially when 

 they are fresh, because, in consequence of their abun- 

 dant contents of water and fat, they are greasy, and 

 without the addition of some dry, pulverulent body, 

 which is capable of absorbing the water and fat, 

 they are not easily beaten to a powder, but ball to- 

 gether into a moist, dough-like mass. That the 

 bone-dust is thus greatly lessened in value is ob- 

 vious; inasmuch as two additions concur to de- 

 teriorate the excellence of the manufactured prod- 

 uct : — first, the water contained in fresh bones, 

 and, second, the lime, which by its powerful affinity 

 for water enters into firm combination with it, and 

 makes it, as it were, fixed. Fresh cylindrical or hol- 

 low bones contain from 3 to 7 per cent., and fresh 

 flat bones from 12 to 20 per cent, of water; If, 

 then, it be assumed that the average contents of wa- 

 ter in a mass of fresh bones about to be converted 

 into powder amount to 12 per cent., and the lime 

 employed to take this into combination to 8 per 

 cent., it follows that, in powder so obtained, 20 

 per cent, of heterogeneous and inefficacious sub- 

 stances are present ; — that it is, therefore, one fifth 

 less valuable than that which is prepared from dry 

 bones, without any addition of lime. 



