88 TIIK'IIOLOGIA MAMMALIUM; 



tliese we have since examined and compared, under the microscope, but can discover no 

 difference between them. 



The cause of the sudden loss of color. As to the manner in which colored hair becomes 

 suddenly devoid of color, no satisfactory explanation is to be found in books. Vauque- 

 lain says " we must suppose that, in these critical moments;, nature undergoes a revolution, 

 and the natural functions are, in consequence, suspended or changed some agent is 

 developed in the animal economy, which, passing into the hair, decomposes the coloring 

 matter," &c., &c. (See Nich. Diet, of Chem., title Hair.) 



As to the cause of this phenomenon we know but little ; probably, as we grow older, the 

 vessels that convey the coloring matter become smaller and less capable of their office, and 

 its circulation is diminished, and finally entirely impeded. 



Of the gradual loss of color in Pile. 



" The glory of young men is their strength, and the beauty of old men is the grey head" (Prov. 20: 29.) 



Hair of the head begins to turn grey at thirty. 



"Grey hairs are sprinkled upon him, but he knoweth it not." (Hosea, 7 : 9.) 



Of the causes of turning grey. Many causes may retard or advance it. We have a 

 lock of hair of Robert Davidson, cut from his head the 9th of January, 1849, on which 

 day he was one hundred years old. It is generally white, (i. e. colorless,) but we find a 

 few Mack hairs. We have another of a young lady, who is only thirteen; a large proportion 

 of the filamenls are brown; but there are many hairs entirely colorless.* Her grand- 

 mother informed us that she had grey hairs when she was born. 



Severe sickness is apt to hasten the whitening of the hair; and we have the authority 

 of Rayner for saying, that long confinement in the dark will have the same effect, f (See 

 Diseases of ihe Skin.) But that light is not absolutely necessary to the existence of the 

 black color of hair, is shown by a lock in our collection, taken from a foetus of 9 months. 

 It is as black as jet. 



Of the Indian turning grey Dr. J. Von Ischudi (in Travels in Peru) says, that "the 

 hair of the head of the wild Indian is long, stiff, and of a brilliant black, (p. 290;) that 

 some of them live to a great age, viz: 120 to 130; that generally they retain their teeth 

 and hair in extreme old age, and that it is remarkable that their hair never becomes white, 

 and very seldom even grey." (p. 340.) "The ancient bodies, found preserved, have 

 always the hair perfectly free from decay." (p. 352.) 



We have, in our cabinet, several specimens of colorless American Indian hair. 



As it is upon the head of man that hair first appears, so it is there where it first loses 

 ils color; then the beard, and lastly the hypogastric hair. It is said that it commences to 

 lose color first at the temples which are so called from the Latin tempus, to 'denote this 

 primordial impress of lime. The last place is the lower part of the head and upper part 

 of the neck. 



Dr. Gross says that, hair [the filament] turns white first at the loose [anterior] 



* We possess a lock of brown hair of Mr. Win. Duffey, aged 70, in which very few grey can be found. 

 t Our American Mummy hair, which has been so many hundred years in the dark, is turned from black to brown ; but 

 this may be owing to Ih? substances used in its preservation. 



