THE TECHNOLOGIST. [August 1, 1864. 



16 ON CHEMISTRY APPLIED TO THE ARTS. 



the formation of new bone on the exterior surface of the bone, while 

 the old substance is removed through the interior duct, and that the 

 composition of the new layer is the same as that of the original bone. 

 Let us now proceed to examine the chemical properties of the various 

 substances composing bones, and some of the various applications which 

 they receive in arts and manufactures. The general composition of 

 bones may be considered to be as follows : — 



Bones. 



{Blood-vessels 1 



Osseine 32 



Fatty Matters 9 



pVater 8 



Phosphate of Lime... ... ... 38 



< Phosphate of Magnesia ... ... 2 



| Carbonate of Lime ... ... ... 8 



L Divers Salts 2 



Organic 



Substances. 



Mineral 

 Substances. 



100 



The above-named animal matter, osseine, C 50"4, H 6 - 5, N 16"9, 

 26 - 2, and which has been erroneously called gelatine, is insoluble in 

 water, weak acids, and alkalies, whilst gelatine presents properties 

 directly the reverse. But what has led to this popular error is, that 

 osseine, when boiled in water, becomes converted into the isomeric 

 substance commonly called gelatine. As I shall have to dwell upon 

 this substance at some length in my next two lectures, I will not detain 

 you now further than to state that osseine is obtained from bones by 

 placing them in weak hydrochloric acid, which dissolves the phosphate 

 of lime and other mineral salts, washing the animal substance, oss6ine, 

 until all aoid is removed, drying it, and treating it with ether to remove 

 fatty matters. I cannot leave this subject without remarking on the 

 extraordinary stability of this animal substance, for it has been found 

 in the bones of man and animals after many centuries, and even in 

 small quantities in fossil bones. 



The fatty matter of bones is made useful in the manufacture of soap, 

 railway grease, and other purposes ; it is obtained by taking fresh bones 

 (as bones which have been kept a long time will not yield their grease 

 easily) and placing the spongy parts, or ends of the bones (where most 

 of the fatty matter exists), in large boilers filled with water, which is 

 then carried to the boil, when a part of the osseine is converted into 

 gelatine, and the fatty matter liberated rises to the surface, and is 

 easily removed. The bones thus treated are called boiled bones, and 

 receive many important applications. Benzine and bisulphuret of 

 carbon have been used as substitutes for water in the above operation, 

 but the advantages do not seem to have been sufficient to lead to their 

 general adoption. 



Mineral Matter of Bones. — These, as the foregoing tables show, are 

 chiefly represented by phosphate and carbonate of lime. The immortal 



