CHAP. X. WORKS OF ART FOUND IN THE GROTTO. 187 



in his restoration of the cave. His artist also has inad- 

 vertentl}^, in the same drawing, delineated the arched grotto 

 as if it were shaped very regularly and smoothly, like a finished 

 piece of masonry, whereas the surface was in truth as uneven 

 and irregular as are the roofs of all natural grottos. 



There was no stalagmite in the grotto, and M. Lartet, an 

 experienced investigator of ossiferous caverns in the south of 

 France, came to the conclusion that all the bones and soil 

 found in the inside were artificially introduced. The sub- 

 stratum, b, fig. 25, which remained after the skeletons had 

 been removed, was about two feet thick. In it were found 

 about ten detached human bones, including a molar tooth ; 

 and M. Delesse ascertained by careful analysis of one of these, 

 as well as of the bones of a rhinoceros, bear, and some other 

 extinct animals, that they all contained precisely the same 

 proportion of azote, or had lost an equal quantity of their 

 animal matter. My friend Mr. Evans, before cited, has sug- 

 gested to me that such a fact, taken alone, may not be con- 

 clusive in favor of the equal antiquity of the human and 

 other remains, although it has no doubt an important bearing 

 on the case, because, had the human skeletons been found to 

 contain less gelatine than those of the extinct mammalia, it 

 would have shown that they were the more modern of the 

 two. But it is possible that after a bone has gone on 

 losing its animal matter up to a certain point, it may then 

 jDart with no more so long as it continues enveloped in the 

 same matrix, so that if all the bones have lain for many thou- 

 sands of years in a particular soil, they may all have reached 

 long ago the maximum of decomposition attainable in such a 

 matrix. In the present case, however, the proof of the con- 

 terajjoraneousness of man and the extinct animals does not 

 depend simply on the identity of their mineral condition. 

 The chemical anatysis of M. Delesse is only a fact in corro- 

 boration of a great mass of other evidence. 



