of sea waters, in different parts of the ocean, &c. 1 6$ 
Edinburgh, * Dr. John Davy, now of Ceylon ,-f and M. 
Gay-Lussac, J have also added many useful facts to this 
part of natural science. These two last observers, in particular, 
have given the specific gravities of waters in a variety of lati- 
tudes, from England to Ceylon, and from South America to 
France, and their results appear to lead to the general conclu- 
sion, that the variations obtained in those parts of the ocean 
were but very slight, and are to be ascribed rather to acci- 
dental causes than to any general principle. § 
The immediate objects of investigation which presented 
themselves to me were, first, to ascertain the specific gravities 
of upwards of seventy specimens of sea water which I had 
procured from different parts of the world ; and afterwards to 
examine whether any differences could be traced in the chemi- 
cal composition of those waters. This naturally gave rise to 
two distinct parts, and afforded a convenient mode of dividing 
the subject. 
§ l .Of the specific gravities of sea waters, from different seas, 
and in different latitudes ; with some remarks on the tempera- 
ture of those seas. 
Before I proceed to state the results, I shall briefly describe 
the mode in which the waters were weighed, and the appa- 
ratus which I contrived for the purpose of raising water from 
the bottom of the sea. 
The specific gravities were taken in the usual mode, that is, 
by comparison with equal bulks of distilled water of the same 
* Edinb. Philos. Trans. Vol. VIII. j- Philos. Trans, for 1817. 
X Ann.de Chim. for Dec. 1817; and Philos. Magaz. Vol. LI 
§ M. De Humboldt ( Personal Narrative,Vol. I.) thought he could perceive that 
