G. GENERAL NATURAL HISTORY AND ZOOLOGY. 165 



of the ingredients in question. While no particular influence 

 seemed to be exercised upon the animal by this novel regi- 

 men, on its being killed and the bones subjected to a chem- 

 ical examination, the particular substance experimented with 

 was found to enter in very considerable quantity into the 

 ash. 6 JB, August 16, 373. 



PERMANENCE OF BONE. 



Karl Aeby discusses the cause of the permanence of the 

 organic substance of bone, and comes to the conclusion that 

 its resistance to putrefaction is a consequence of the small 

 quantity of water it contains, which, besides, is in chemical 

 combination, fresh bones having about eleven or twelve per 

 cent, of water and twenty-eight of organic matter. As a 

 proof that the water is combined chemically, Mr. Aeby men- 

 tions that thoroughly dried and finely pulverized bones, when 

 moistened, become considerably heated (one gram of bone 

 evolving about twelve units of heat). This chemically com- 

 bined water seems to act the part of water of crystallization, 

 and can not induce putrefaction, while the rigidity of the in- 

 organic substance prevents swelling i. e., the reception of 

 more water from the outside. Crushed and finely pulverized 

 bones, on the contrary, swell by soaking, and then speedily 

 putrefy. 18 (7, 1871, xvn., 266. 



DESTRUCTIBILITY OF HUMAN BONES. 



Mr. Pengelly, in the Quarterly Journal of Science, in reply 

 to a question which has often been asked as to the reason 

 why we do not find the bones of the men who made the un- 

 polished flint implements as well as the implements them- 

 selves a doubt thereby being thrown upon the human origin 

 of these articles takes occasion to show, by a careful colla- 

 tion of the evidence on the subject, that human bones have 

 been found in repeated instances by reliable observers in Eng- 

 land, France, Belgium, and elsewhere; and furthermore, that 

 even if nothing of this sort were discoverable, human agency 

 in the production of these implements is as distinctly shown 

 as the print of a naked foot proved to Robinson Crusoe the 

 presence of a second human being on his desert island. He 

 also shows that there is a great difference in the bones of 

 different animals as to the length of time their remains are 



