256 Foreign Correspondence. 
Art, XXIX.—foreign Correspondence. 
1. On the Science of the International Exhibition. In a letter from O.C, 
Marsg, B.A., to Prof. Smuman, dated London, Noy. 25, 1862. 
Tue International Exhibition, which has just closed, contained many 
objects of considerable scientific interest; and, in accordance with your 
request, I shall endeavor to give a short account of those which seemed 
most worthy of notice. 
interest, and the pr for its separation, which were shown theorel 
ically and practically, are generally well known, There was, howevély 
gold by chlorine water, which seemed worthy of more attention than 
received. The material used is auriferous mispickel, from which the at 
senic is first separated by roasting.’ 
Silver.—The silver, exhibited in Class I, possessed few points worthy 
of mention, many of the most important mines not being re resented, 
and others very inadequately. Some beautiful specimens of native silver 
were shown from the government mines of Kongsberg, Norway, 4% of 
from the Copper mines of Lake Superior; and a good collection 
various ores from the Washoe mines of California. Specimens of — 
glance, horn-silver, and ruby silver, from a new locality in Newfound 
were also exhibited. 9 
um, and 
its 
uthenium, 
dr as 
* The numbers refer to the Official Catalogues of the various departments. on 
2 A series Rei in specimens illustrating Plattner’s process W#* 
hibited in the American Exhibition of 1853, No. 278, Class I. 
