Beast 
J. D. Whitney on changes in Mineral Veins. 53 
sea leaves the cause thus assigned to operate with full power ; and 
if Schulten’s hypothesis be confirmed, of which there is now 
but little doubt, it will, in all probability, serve to explain similar 
phenomena observed in other close waters, as the Caspian, Lake 
Balkai, and the Lake of Geneva, to which Saussure has asses 
similar causes.” 
[An important paper on the fluctuations in the surfaces of the 
Lakes not referred to by Major Lachlan is published by Charles 
Whittlesey in Foster and Whitney’ s Report on the Lake Superior 
Land District, Part 2, 1851, p. 319. It reviews the facts, adds a 
large number of observations and sustains the conclusion that the 
rise is not periodical.—Eps. | — 
Pe al 
tT. V.—Remarks on the changes which take We in the 
Btrsinaeles and Composition of Mineral Veins near the surface, 
with particular reference to the East Tennessee Copper Mines ; 
y J. D. Wurrney. 
Ix the number of the American Journal of Science for March last, 
([2] xix, 181,) M. Tuomey has given “‘a brief notice of some facts 
connected with the Ducktown, Tennessee, Copper Mines.” As 
region alluded to, I take the liberty of stating what I conceive to 
e the correct interpretation of the phenomena displayed on so 
large a scale in the Polk Courity, or Ducktown Mines. 
tr. Tuomey remarks as follows: ‘in every published account 
of the mines that I have seen, the impression is er ig the ore 
(5) is derived from the underlying portion of the bed (c) by de- 
composition.” No such impression could, by any pals Pa be 
derived from the descriptions of the East ‘Tennessee Mining re- 
gion which I have published. 'To show this, I quote from the 
reporty to which Mr. Tuomey refers, at the commencement of his 
notice, as follows: ‘On. penetrating beneath the surface, the sec- 
tion represented in the annexed figure is obtained. (See section 
accompanying Mr. Tuomey’s article.) Beneath the gossan, is 
found a bed or mass of black cupriferous ore, of variable thick- 
hess and width. This, as well as the gossan, is the result of the 
decomposition of an ore consisting originally of a mixture of the 
sulphurets of iron and copper, which was associated with a quartz- 
Ose gangue or. vein-stone. The place of the bed of copper ore 
marks the limit of the decomposition of the vein ; beneath it the 
sf + Report see East 7 i he and ae Copper Mining 
; byJ. D. Whitney. New York, 1853. 
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