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[Assembly 
in the ordinary way on a small scale, has shown, that the iron obtained 
from it was of the best kind. 
This is the mineral which has made some noise as a silver ore, which 
it was calculated to do from its unusual appearance and its great quan- 
tity. Many satisfactory experiments are cited in proof of its containing 
silver, all which experiments are negatived not only by the non-exist- 
ence in nature of any ore of silver of the kind, but by the fact, that sil- 
ver will not unite to carbon, nor will it unite with iron in greater amount 
than one five hundredths. In combining silver with steel for the pur- 
pose of increasing its hardness for razors and other instruments requiring 
a keen edge, it has been found that when more than the quantity just 
named is fused with that metal, the silver exhibits itself throughout the 
mass in the form of filaments or threads ; now no such appearance was 
visible in the experiment made to ascertain the quality of the iron 
which the ore would produce. 
The chemical department of the survey belonging to Dr. Beck, an 
analysis of the ore no doubt will be given by him and which will be 
decisive of its nature. 
The plumbago ore is connected with steatitic masses, some green, 
white, black, 6cc. Likewise with dark greenish masses, containing 
pyrites, the kind connected with the base of the specular ore. I also 
noticed a peculiar porous rock, with fine scales of plumbago, which I 
met with in another locality near Sommerville, between Parish's and 
Kearney's ore beds. 
The plumbago ore shows itself on Mr. Cleaveland's land in several 
places on the side of a hill, back of which at no great distance are the 
usual gneiss and granite masses, and I should judge that the whole of 
the product noticed, were an overlying deposit to these rocks, and 
analogous as to cause, origin and position, to the second and third de- 
posits of iron already mentioned. 
As natural bridges are not of frequent occurrence, a word in passing 
seems to be necessary. The bridge exists at the bend of a branch of 
Indian river near to the village of its name. It is formed merely by a 
cavity or fissure in the primary limestone which there abounds as an 
associate of the usual granite gneiss rocks. A portion of the water 
passes by the cavity, whilst other portions pass round the bend and un- 
der the wooden bridge beyond. 
