132 TRICHOLOniA MAMMALIUM; 



The fat (says this author) may be extracied by boiling the hair in alcohol; and is, ordi- 

 narily, acid, (the margaric and oleic.) It has a blood-red tinge in red hair; greyish-grey 

 in brown hair, and (according to Jahn's, in Der Haarartz, ti. p. 49,) white hair* has a 

 limpid oil. 



After the extraction of the fat, brown hair becomes greyish-yellow, and then behaves 

 like horn. 



Hair is insoluble in water, whether cold or hot; but in Papin's Digester is dissolved 

 (all except the fat) with a disengagement of sulphuretted hydrogen. The residue of the 

 liquid, after evaporation, is viscous, and capable of being re-dissolved in water, when it 

 does not become a jelly. From its watery solution a precipitate may be thrown down by 

 concentrated acids by chlorine by the sub-acetate of lead, and by tannic acid. 



When hair is dissolved in concentrated acids (particularly by the nitric) the colored oils 

 separate, coagulate by cold, and become limpid 



Chlorine whitens hair and produces, by its combination with it, a viscous transparent 

 mass, which has a bitter taste, and dissolves in water and alcohol. Caustic potash, 

 diluted, dissolves hair entirely. 



Hair may be dyed, melted and distilled. Hair may be colored by the metallic salts both 

 nitrate and sulphate; nitrate of silver blackens it When heated, hair melts, exhaling an 

 odor of horn. It burns with a sooty flame, leaving a bloated coal. 



Upon dry distillation, hair gives off one-fourth of its weight of a carbon diffic/ult to 

 incinerate, the products being empyreumatic oil, water charged with ammonia, and com- 

 bustible gases which contain sulphuretted hydrogen. 



Van Laer is of opinion, that hair consists, essentially, of a substance nearly allied to 

 gelatine and bisulphuret of proteine.f This substance has the formula of carbon, 13; 

 hydrogen, 10; nitrogen, 3; oxygen, 5, and gluttin (which is the form of gelatine which is 

 obtained from the skin, from serous membrane, from hoof, from bone, from tendon, and 

 from cartilage,) having the formula of carbon, 13; hydrogen, 10; nitrogen, 2, and 

 oxygen, 5. 



There have also been found in hair silica, iron and manganese. 



The elements of Pile in the blood and in the milk, That the blood contains all the 

 elements of hair, is found by its being produced on the foetus; and that the mother's milk 

 is equal, in this respect, is demonstrated by the growth of the hair while a child is receiv- 

 ing no other nourishment. 



The ancient practice of milking the ewes, to make butter-cheese, was believed to have 

 injured the growth of the lamb's wool. (See Lib. of Use. Knowl., p. 48.) 



OF EXAMINING PILE. It often becomes necessary, while examining a hair under the 

 microscope, to turn it over and back again, or halfway over a task not easily performed. 



* He here speaks of white (albinos) hair, and not grey (colorless) hair, as \vo venture to presume. 



t Proteine is the name given to the substance which enters into the three important animal compounds, albumin, fibrin, 

 and 



