506 BONES. 



After thorough drying, flesh leaves behind only 

 about 23 per cent, of solid substance, the remaining 

 77 per cent, are water. Of the solid residue about 6 

 per cent, are soluble in water; chopped meat, after 

 being extracted with water, leaving behind only 17 

 per cent, of solid substance. 



The reddish fluid expressed from fresh meat has an 

 acid reaction from the presence of free lactic acid and 

 acid phosphates of the alkalies ; it coagulates when 

 heated. The clot is albumen, colored by a brownish- 

 red coloring matter, very similar to, and probably 

 identical with, haemoglobin (p. 494). Acetic acid and 

 rennet also show the presence of casein. 



It contains, further, creatine (p. 248), sarcine (p. 246), 

 xanthine (p. 246), inosite (p. 197), dextrin (p. 207), 

 sugar (flesh-sugar, probably identical with grape-sugar), 

 an acid, inosic add, as yet but little known; and salts, 

 particularly potassium paralactate and phosphate, the 

 potassium salts of volatile acids (butyric, acetic, for- 

 mic(?)), potassium chloride, and magnesium phosphate. 

 Sodium chloride and calcium phosphate are only pre- 

 sent in small quantity, and sulphates not at all. 



Greatine, xanthine, sarcine are intermediary products 

 of the process of waste in muscular tissue. 



9. Bones. 



Bones excel all other organs in the large amount of 

 inorganic matter (earthy matter) contained in them. 

 Thin lamellae of compact bony tissue appear under 

 the microscope as an homogeneous, structureless, trans- 

 parent mass, which is traversed by small canals (the 

 Haversian canals), containing fat and vessels; and, in 

 the interstices between these, by minute, regularly 

 arranged cavities, with numerous fine tubes issuing 

 from all parts of their circumference. 



If a bone is placed in very dilute hydrochloric acid, 

 the earthy matter is extracted, and the organic por- 

 tion, cartilage, interwoven with all the fine vessels and 

 membranes, contained in the bone, remains behind as 

 a flexible, soft, translucent mass, having the form of a 



