Chemical Conditions of the Water, §c. 241 
Ant, XXX.—On the different Chemical Conditions of the Water 
at the surface of the Ocean and at the bottom, on Soundings ; 
y Aue. A. Haves, Assayer to the State of Mass. 
Coysiperine the surface, which the ocean covers in compari- 
son with any large extent of land surface, we might be led to 
expect a want of uniformity in the distribution of saline matter 
throughout its mass. Those parts reposing in immediate contact 
with saline deposits and many decomposing rocks, would every 
instant receive more soluble matters than contiguous portions, 
and while matter to be dissolved remained, the balance of distri- 
bution would be disturbed. Local differences are known to 
exist and are referred to the influence of evaporation, and to lower 
and upper currents, with great degree of probability. Still, the 
belief that the water of the ocean has existed during the lapse 
of great geological periods of time, with the same or even a 
large proportion of saline matter, must gradually give way, as 
facts connected with the decomposition of rocks are attentively 
ied. 
_ The phenomena which form the subject of this communica- 
tion, are only remotely connected with this point of unequal dis- 
tribution ; being related to kind, rather than quantity of saline 
ts. 
The mass of ocean, exposed on its surface to the mixture of 
gases forming our atmosphere, absorbs both constituents, the 
oxygen in the larger proportion. Winds greatly favor this effect, 
and the increased quantity found in the water after storms, is 
referred to this action. 
-When ocean water, taken at the same moment from the sur- 
face and only one to two hundred feet under this surface, is sub- 
jected to the usual course of analysis, a larger proportion of 
oxygen is constantly found in the surface samples. Trials, made 
at points from the temperate to and within the torrid zone, cor- 
responded, and only slight deviations were found in the moving 
water of the Gulf Stream. Another kind of evidence of this 
fact, is afforded by the observations made on the corrosion, of the 
Copper sheathing of vessels. Slight inequalities in the kinds of 
Copper used exist; but when a large number of cases are included 
and time of observation is considerable, this influence is hardly 
Seen. It is a general law, that copper sheathing corrodes most 
Tapidly at those parts of the covered surface, where, by agitation, 
the most air is dissolved in the water passing in contact with it, 
The fact is well known, that sea-water, deprived of air, has no 
“lon on copper even after many years’ exposure, and this relation 
becomes changed, when we allow the same water to dissolve air. 
Some persons who have noticed this uniformity of corrosion, at 
Steon Sunes, Vol. XI, No. 32.—March, 1851. 3 
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