78 ANATOMY. 



the bones have been said to contain proportionally more earthy mat- 

 ter, but this is doubtful. In the disease called rickets, they contain 

 less. In children, the carbonate of lime is, relatively to the phos- 

 phate, less abundant. 



The purest form of the muscular tissue, the substance of the vol- 

 untary muscles, contains about 74.5 per cent., or nearly three-fourths 

 of its weight of water. The remaining fourth, or 24.5 per cent., 

 which is solid matter, consists of 15 parts of muscle-fibrin or syntonin, 

 and of a residue, of which from 2 to 4 parts are fat, the rest being 

 albumen (probably derived from moist fluid between the fibres, and the 

 blood in the capillary vessels of the muscle), gelatin (derived from the 

 intermixed fine areolar tissue), traces of a red pigmentary substance, 

 a large quantity of extractive^natters, such as creatin and creatinin, 

 acids, and a quantity of alkaline and earthy salts, with some carbonic 

 muscle-sugar or inosite, lactic, butyric, formic and acetic acid, and 

 oxygen. The juice of muscle is acid. It contains more potash than 

 soda salts, a large proportion of which are phosphates. The substance 

 formerly called ozmazome, on which the odor of muscle depends, is 

 a compound of several of the extractive matters. 



The white and gray nervous substances resemble each other in con- 

 taining, like the rest of the soft tissues, a very large percentage of 

 water; the solid residue is composed of albuminoid matter, a large 

 quantity of fatty matters, extractives, and salts. They differ from 

 each other remarkably, in the relative proportions of their constitu- 

 ents. The white substance contains more solid matter and less water 

 than the gray, the percentage in the white matter being 73 of water 

 to 27 of solid substances, and in the gray matter 85 of water to only 

 15 of solids. The white matter contains 15 per cent, of fat, the gray 

 only 5 per cent. : the white has 10 per cent, of albuminous matters, 

 the gray only 7 J : the extractive matter and the salts are about the 

 same, the latter being chiefly phosphates. Amongst the albuminoid 

 substances, is one said to resemble syntonin, and another which is 

 compared to elastin. The fatty matters are partly reddish and partly 

 colorless : they consist of cerebric acid (a peculiar azotized acid), gly- 

 cero-phosphoric acid, lecithin, palmitin, palmitic acid, with traces of 

 olein and some cholesterin. These fatty substances are supposed to 

 be chiefly present in the medullary sheath, whilst the axis band is 

 believed to contain the albuminoid syntonin. The extractives consist 

 of creatin, xanthin, hypoxanthin or sarcin, and inosite, with lactic, 

 phosphoric, and even uric acids, combined with potash, lime, and mag- 

 nesia. There are also traces of oxide of iron, silica, alkaline sul- 

 phates, and chloride of sodium. The phosphorus specially contained 

 in the brain amounts to from 1.3 to 1.79 per cent, of the weight of its 

 substance. 



The proximate constituents of the blood are so various, that, chemi- 

 cally speaking, it contains nearly all the substances found in the solid 

 tissues, either as its essential constituents, or as unavoidable or occa- 

 sional impurities. There is one very remarkable exception to this 

 statement, in the total absence from the blood of any gelatin or chon- 

 drin, or of any substance which yields gelatin or chondrin on being 



