210 



THE GEOLOGIST. 



above ; its temperature being also slightly lower ^ showing that 

 the density of the sea is comparatively little influenced by 

 superincumbent pressure. Other experiments are recorded 

 in the same work, but they are not of so conclusive a 

 nature, although they in general confirm the above opinion 

 as to the temperature of the greatest density of sea water; 

 for the density is very much affected by the different quan- 

 tities of saline matter held in solution, and also by the 

 presence or absence of medus(B and marine animalcules. 



The following table, composed from the same work, shows 

 the quantity of saline contents, as well as the specific gravity 

 and temperature of the sea at the surface : — - 



Lat. Long. Specific Temp, at Colour, Sal. Mat. 



Grav. Surface. per cent. 



64 26 0 38 1-0269 43 5 Ultra M. Blue. . . . 3-54 



66 45 1 0 . . . r0263 43 5 Ultra M. Blue 3.79 



69 14 3 0 1-0269 38 0 Ultra M. Blue 375 



71 10 5 30 1-0269 39 0 Ultra M. Blue 3-75 



74 34.... 10 0 1-0267 32 0. ...Blue 3*77 



76 33 10 20 r0267 33 0 Blue 3*60 



77 30 6 10 r0263 28 5 Olive Green 3*42 



77 34 8 0 1-0267.... 38 0 Blue 3*70 



78 25.. . 8 20 1-0265.... 31 0 .... Olive Green 3*91 



78 30 6 30....r0265 29 0 Blue 3-88 



78 35... 6 0.... 1-0261 29 0. ... Olive Green 3*27 



It may be remarked on the foregoing table, that the ob- 

 servations T, 3, and 4, in which the temperature was near 

 that of the greatest density of fresh water, the specific gravity 

 was also greatest; M'hilst in the observations 9 and 10, in 

 which are found the largest portion of saline contents, the 

 temperature being considerably less, the specific gravity is 

 the smallest recorded, with the exception of 7 ^^^^ 

 which contain the smallest quantity of saline contents. The 

 other observations generally favour the conclusion, that the 

 sea is at its greatest density at or near to the temperature of 



