1818.] On Alimentary Matter from Bones. 107 



jected ; one by which what is called the " gelee " is obtained from 

 them ; and the other a complicated operation by which the 

 " gelatine" is procured. In the first operation the bones are 

 well washed, and are then broken into small fragments, with a 

 mallet on a hollow block ; they are then boiled in a common 

 vessel for three hours ; no compression is employed, nor is the 

 water raised above the boiling point ; J- part of its weight of 

 bones is added to the water, and during the process the fat 

 which rises to the surface is skimmed off, and afterwards added 

 to the product. By this means a jelly is procured, which is 

 generally strong enough to become concrete on cooling. The 

 bones may be boiled again three successive times, and still 

 furnish a considerable quantity of jelly ; by four boilings of three 

 or four hours each, 1 lb. of bones will furnish 4 lb. of jelly, 

 which is supposed to contain as much nutritive matter as com- 

 mon soup made from 6 lb. of meat. 



In order to preserve the bones, when they are collected in 

 large quantity, and during warm weather, after having been 

 washed and broken, they are to be boiled in water for half an 

 hour, in order to deprive them of the fat and marrow which they 

 contain ; they are then boiled for half an hour in a caustic alka- 

 line ley, and after being well dried in the open air, they may be 

 preserved for years if they be kept dry. The alkaline liquor is 

 formed by adding l-i- lb. of common potash, and the same quan- 

 tity of quick lime, to 50 lb. of water ; the clear fluid, when drawn 

 off, is sufficient for 1001b. of bones. 



In the second process, to procure what is termed the " gela- 

 tine," the process that has been described above is to be 

 employed in the first instance, to extract all the parts that are 

 soluble by boiling, after which the bones arc in a proper state 

 for this further process ; old bones, however dry they may 

 appear, are equally proper for it. The object of it is stated to 

 be, not to procure the " gelee," but the proper " gelatine," 

 which is chemically united to the phosphate of lime. The agent 

 employed is diluted muriatic acid; 1001b. of the bones require 

 501b. of acid and 150 of water ; the digestion is to be continued 

 for three weeks, at a temperature of about 65°. The bones by 

 this process are deprived of all their earthy matter ; they are 

 then well washed in water for 24 hours ; the outside membrane of 

 the bone is pared off, and serves for the making of glue. The 

 remainder of the bones is then dried in the open air ; it consists 

 entirely of the compact " gelatine," and, if kept diy, may be 

 preserved for an indefinite length of time, without undergoing 

 any alteration. About -i of the weight of the entire bone con- 

 sists of this " gelatine ;" by being macerated for some hours in 

 tepid water, and afterwards boiled over a slow fire, it is dissolved, 

 and composes a highly nutritive soup. It is estimated that one 

 ounce of the dry " gelatine " is equally nutritious with 1 lb. of 

 meat. 



