Analysis of the Human Teeth. 313 



OH of peat dissolves in abundance in alcohol, by means 

 of disestion. This solution, which is clear, becomes fixed 

 by cooling. Maltha with alcohol exhibits the same phe* 

 iioniena. 



LVII. Analysis of the Human Teeth. By W. H. Pepys 

 jnn. Esq. P.R.I., Memher of the Askesiun and BrUish 

 Mineralogical Societies *. 



Mr. Charles Hatchett, in his valuable paper on shell 

 and bone, (Philosophical Transactions for 1799,) enume- 

 rated the several substances which enter into iha composi- 

 tion of the human teeth: it is to be regretted that the na- 

 ture of his subject did not render it necessary for hini tq 

 ascertain the proportions in which they are respectively 

 found, as it could not have tailed to have proved highly 

 pseful, and his known accuracy would have precluded the 

 necessity of any other person undertaking such a labour. 

 Several good analyses of bone have been published, but I 

 believe no accurate analysis of the teeth has yet been of-: 

 fered. 



Bone, it has been observed, when exposed to the actioii 

 of acid menstrua, becomes dissolved ; that is to say, the 

 Golid or constituent substance of them is abstracted, and a 

 gelatinous matter is left of the form of the original bone. 



Nitric, nmriatic, and acetic acids are capable ot pro- 

 ducing this change, which is accoinpanied with a liberation 

 of an aeriform fluid, that precipitates lime in lime water, 

 changes veiictablc bines red, and by its gravity is known 

 to be carbonic acid gas. These acid solutions yield a co- 

 pious precipitate with pure ammonia, which is again solu- 

 ble in either of the acids. After the precipitation by pure 

 ammonia, the solution of the carbonate of ammonia will 

 Still produce a new precipitate. 



The precipitate of the first solution by pure ammonia, 

 as noticed above^ is soluble again in the acids before men- 

 substances apnears to him improper in vanous respects. Might not 

 maltha be the' product also of the distillation of a similar kind of turf 

 effected by nature ? As that which forms the subject of the preceding 

 analysis can no longer be classed among the bituminous fossils, both on 

 account of its chemical principles and of its mineralogical characters, 

 hi old deBnition of bituminous ligneous earth can no longer be applied 



** 'f' , TT r u 



• From a recent interesting publication, Tbe hatural llsiory of toe 



J '.[",'"; Iceth, by Jgseph Fox. . , 



^ lioncd; 



