240 Miscellaneous Notices in Mineralogy, Geology ^ ^c, 



country, and is creditable both to the patrons and agents irs 

 this work, which appears to be executed with laudable fidel- 

 ity and aljility. We wish it may be followed by similar ef- 

 forts in other parts of this country. We observe also, among 

 numerous other important subjects discussed in the fourth 

 volume of the Transactions of the Society for the promo- 

 tion of useful arts in the state of New-York, an elaborate 

 paper on alum, by one of the obove gentlemen, namely, Dr. 

 Theodore R. Beck. 



He has concentrated much useful information on this im- 

 portant practical subject and the paper may be advanta- 

 geously consulted by those who wish to obtain the most im- 

 portant facts without the trouble of consulting numerous au- 

 thors. 



Dr. Beck's memoir contains the following remarkable 

 fact : — A distinguished American general was interred, sev- 

 eral yeai's since, at the town of Erie, on the border of the 

 lake of the same name. His son, three or four years ago, 

 removed the remains to Chester county, in Pennsylvania. 

 " On raising the body, it was found in a high state of pres- 

 ervation, so much so, that the features were readily recog- 

 nized by those who had previously known the general. The 

 flesh was indurated to such a degree that it could not be 

 separated from the bones by a knife."* 



In short, the body appears to have been a perfect natur- 

 al mummy ; the preservation is imputed to aluminous salts 

 which abound so much there that " quantities of crystalized 

 alum are found on the surface of the ground." 



20. Alum in decomposed m,ica slate. 



Among the sources of alum, there is one which we have 

 never seen mentioned by any author. It is from the decom- 

 position (net of clay slate, which all authors mention, but) 

 of mica slate. We have been frequently presented with 

 specimens of alum formed in decomposed mica slates, as 

 from the towns of Preston, Waterbury and Hunting- 

 ton, in Connecticut, and indeed we have seen but a few 

 instances of American alum, derived from any other source. 



* If we are not in an error, this body had been interred more than twen- 

 ty years. — Ed. 



