320 



Atomic Weight of Mercury. 



Example OF Table ii.— Con vert 2205.23 Toiees 

 Cbeight of Mount Blanc above the Lake of Ge 

 neva) into English Feet. 



2205.23 



14102,33 



Example OF Table III. — Gay Liissac ascended 

 with a balloon to the height of 7028.3 Metres, as 

 determined by a barometer, — convert this into 

 English Feet. 



Metres. Eng. Feet. 



7000 = 

 20 = 



7028 3 = 



22J06,29 



65.62 



26.23 



0.98 



23059.H 



4 Miles 1939 Feet. 



TABLE IV. REDUCTIOPf OF DECIMETRES, CE^TIMETRES, AND 



MILLIiaETRES, TO ENGLISH INCHES. 



From De La Beches Geological Manual. 



ON THE ATOMIC WEIGHT OF MERCURY. 

 To the Editor of the Monthly American Journal of Geology, SJc. 



Sir, — I beg leave to call your attention to a matter, which, 

 though brought before the scientific public some time since, 

 seems not to have received that attention from chemists, which 

 its importance ought to command. 



Three years ago, Mr. S. Allinson, jr. of your city, published 

 an article in Silliman's Journal, in which he maintained that the 

 atomic weight of mercury, as stated in the current treatises on 

 chemistry, was incorrect, and offered several good reasons for his 

 opinion. This article (in a much improved and enlarged form) 

 was subsequently published in the Journal of the Philadelphia 

 College of Pharmacy, for July, 1829 ; and to this Journal I would 

 refer those who may wish to see the experiments and observa- 

 tions, which induced Mr. A. to call in question the correctness of 

 the commonly received statements. Now I desire that some 

 practical chemist or any one else, who may have the apparatus 

 and skill requisite, would decide who is in the right. Mr. A., or 

 the text books. 



The doctrine of chemical equivalents is very justly regarded 

 as one of the most interesting and important departments of 

 chemistry; and it is certainly much to be desired that every thing 



