On Sulphurets of Copper from the Canton (Ga.) Mine. 409 
The transit-instrument is similar to the meridian-cirele, so far 
as the latter is an instrument for the measurement of right as- 
cension. It is the property of the Coast Survey of the United 
States, whose enlightened chief has authorized its employment 
at the Dudley Observatory for the present. The object-glass 
Ne a clear aperture of 72 French lines, and a focal length of 8 - 
eet 
In both these instruments the Ys are so constructed that the 
level-arm may rest upon that part of the pivot which supports 
the instrument. _ 
Art, XXXIX.—On two Sulphurets of Copper from the Canton 
(Ga.) Mine; by N. A. Pratt, Jr. : 
found intimately associated, while at the same time their crystal- 
lographic characters differ so widely,from the above-mentioned 
Species, and especially as they present a form in which they have 
never before been observed, they assume a mineralogical import- 
ance which demands an investigation of the conditions and man- 
her of their occurrence. 
The geological position and character of this mine, as well as 
the unusual variety of minerals occurring here, have been 
the subject of a special and very flattering report by Prof. C. U. 
IS itself slioht] talcose and a é 7 
feet wide. oT is whole series trends N. 65° E., and dips to the 
southeast at an angle varyl from 60° to 80°.. Whether thes are 
altered beds of the ‘Lowe elgcan such as those of Southea 
tennessee, and known as metamorphic Paleozoic, or belon 
I think, however, on account of their distance from the Silurian 
Bees i inclination of 
found to be- 
