414 BONES 



found also the ratio of tho carbonate of lime to the phosphate to be generally greater. 

 In the bones of amphibia, he found less inorganic matter than in those of mammals 

 and birds ; and in the bones of fishes, the earthy matters vary from 21 to 57 per cent. 

 The scales of fishes have a composition somewhat similar to that of bone, but they 

 contain phosphate of lime in small quantity only. 



In certain diseases (the craniotabes in children), the earthy salts fall in tho spongy 

 portion of the bone as low as 28-16 per cent, of the dry bone ; and in several cases the 

 proportion of earthy matter was found by Schlossbergor as low as 50 per cent. At 

 the age of 21 years, the weight of the skeleton is to that of the whole body in tho 

 ratio of 10*5 ! 100 in man, and in that of 8*5 .' 100 in woman, the weight of tho body^ 

 being about 125 or 130 Ibs. 



The quantity of organic matter in fossil bones varies very considerably : in some 

 cases it is found in as large a quantity as in fresh bones, while in others it is alto- 

 gether wanting. Carbonate of lime generally occurs in far larger quantity in fossil 

 than in recent bones, which may arise from infiltration of that salt from without, or 

 from a decomposition of a portion of the phosphate of lime by carbonic acid or car- 

 bonates. Magnesia often occurs in larger quantities in the fossil remains of verte- 

 brated animals than in the fresh bones of the present animal world. Liebig found 

 in the cranial bones excavated at Pompeii a larger proportion of fluoride of calcium 

 than in recent bones ; while, on the other hand, Girardin and Preisser found that this 

 salt had greatly diminished in bones which had lain long in the earth, and, in some 

 cases, had even wholly disappeared. 



The gelatinous tissue of bones was found by Von Biria to consist of 



Recent ox bones Fossil bones 



Carbon 50-401 . . . 50-130 



Hydrogen . . . 7'111 . . . 7'073 



Nitrogen .... 18-154 . . . 18-449 



Oxygen 24-119 . . . 24-348 



Sulphur 0-216 



This is the same composition as that of the gelatinous tissues. 



In the arts bones are employed by turners, cutlers, manufacturers of animal char- 

 coal, and, when calcined, by assayers, for making cupels. In agriculture, they are em- 

 ployed as a manure. Laid on in the form of dust, at the rate of 30 to 35 cwts. per acre, 

 they have been known to increase the value of old pastures from 10s. or 15s. to 30#. 

 or 40s. per acre ; and after the lapse of 20 years, though sensibly becoming less valu- 

 able, land has remained still worth two or three times the rent it paid before the bones 

 wore laid on. In the large dyeing establishments in Manchester, the bones are boiled 

 in open pans for 24 hours, the fat skimmed off and sold to the candle-makers, and the 

 size afterwards boiled down in another vessel till it is of sufficient strength for stiffen- 

 ing the thick goods for which it is intended. The size liquor, when exhausted or no 

 longer of sufficient strength, is applied with much benefit as a manure to the adjacent 

 pasture and artificial grass-lands, and the exhausted bones are readily bought up by 

 the Lancashire and Cheshire farmers. When burned bones are digested in sulphuric 

 acid, diluted with twice its weight of water, a mixture of gypsum and acid phosphate 

 of lime is obtained, which, when largely diluted with water, forms a most valuable 

 liquid manure for grass-land and for crops of rising corn ; or, to the acid solution, 

 pearl ashes may be added, and the whole then dried up, by the addition of charcoal 

 powder or vegetable mould, till it is sufficiently dry to be scattered \vith the hand 

 as a top-dressing, or buried in the land by means of a drill. 



In France, soup is extensively made by dissolving bones in a steam heat of two or 

 three days' continuance. Respecting the nutritive property of such soup, Liebig has 

 expressed the following strong opinion : ' Gelatine, even when accompanied by the 

 savoury constituents of flesh, is not capable of supporting the vital process ; on the 

 contrary, it diminishes the nutritive value of food, which it renders insufficient in quan- 

 tity and inferior in quality, and it overloads the blood with nitrogenous products, the 

 presence of which disturbs and impedes the organic processes.' The erroneous 

 notion that gelatine is the active principle of soup arose from the observation that 

 soup made, by boiling, from meat, when concentrated to a certain point, gelatinises. 

 The jelly was taken to be the true soup until it was found that the best meats did not 

 yield the finest gelatine tablets, -which were obtained most beautiful and transparent 

 from tendons, feet, cartilage, bones, &c. This led to an investigation on nutrition 

 generally, the results of which proved that gelatine, which by itself is tasteless, and 

 when eaten excites nausea, possesses no nutritive value whatever. 



The fol(pwing Tablo exhibits tho relation between the combustible animal matter 

 and the mineral substances of bones, as found by different observers : 



