100 NATURAL HISTORY OF 



surface in the shape of a mere pellicle: this being 

 extracted, weighed eleven grains. In the other vessel, 

 a quiet and gradual escape of gas took place. In the 

 space of seven hours, the earthy matter had been ex- 

 tracted to one-half of the depth of the piece ; and, 

 after the process was complete, it remained at the bot- 

 tom, and retained the original form of the immersed 

 fragment. It was fibrous, soft, highly flexible, and 

 elastic, and weighed eighteen grains. By adding sul- 

 phuric acid to the liquor, after removing the masses of 

 animal matter from both vessels, sulphate of lime was 

 obtained ; and, when weighed, they were found to cor- 

 respond very nearly. The fastidious caution of Mr. 

 Bellamy did not suffer him to regard this experiment 

 as conducted with the greatest nicety. At our request, 

 he submitted a metatarsal bone of Hyaena, from the 

 same cavern, to immersion in one-sixth of muriatic 

 acid to five-sixth's of water ; but, in this case, after 

 the earthy matter was thrown off, the animal substance 

 remained so abundant, that the bone retains its com- 

 plete form, is only translucent, and remains at the 

 bottom of the liquor, as if it were a recent specimen, of 

 which it preserves all the. characters. 



Pieces of human skull, from a sub-Appennine cavern, 

 in Tuscany, probably not less than twenty-five or thirty 

 centuries old, appeared thoroughly fossilized, or rather 

 entirely deprived of animal juices, and in a chalky . 

 state. On examination, in proper chemical tests, by 

 Dr. Armstrong of the Royal Naval Hospital at Ply- 

 mouth, and by Mr. Oxland chemist, both gentlemen 



