364! SUTHERLAND, DAVIS' STRAIT AND BAFFIN'S BAT. 



Europe,* as the analogy between the North Atlantic and Davis' 

 Strait with respect to currents will easily occur to us. 



The specific gravity of the water also assists in determining the 

 direction of the currents in the Polar Seas. During Captain 

 Inglefield's late voyage, it was found to decrease as we approached 

 Cape Farev;ell and advanced northward and westward in Davis* 

 Strait, t 



In the Atlantic, long. 30°, lat. 56° 30', 24th October 1852, the natural tem- 

 perature being 48° Fahr., the density at 60° Fahr. was 1-02808. 



At Cape FareAvell on the 31st July, natural temperature 33°, density 1 •0245. 



Davis' Strait, lat. 68°, sixty miles off the coast of West Greenland, August 

 llth, natural temperature 40°, depth fifty fathoms, density 1 -0265. 



Close to Cape York, lat. 76°, August 21 st, natural temperature 30°, sea-water- 

 ice and icebergs abundant, depth fifty-four fathoms, density 1*0215. 



About two miles off Cape Alexander, Smith's Sound, lat. 78° 20', long 71°, 

 August 27th, natural temperature 32° no ice but in the vicinity of the 

 glaciers in the coast, depth 154 fathoms, density 1-02516. 



In Jones' Sound, lat 76° IV, long. 83° September 1st, natural temperature 

 30°, sea-water-ice and icebergs present but not abundant, density 1 - 02451 . 



About two miles off Cape Fitzroy, Lady-Anne's Strait, Jones' Sound, lat 75^* 

 35^ September 2nd, natural temperature 30°, sea-water-ice thirty to forty 

 feet thick, most abundant, no bottom, 150 fathoms, density 1*0235. 



And off Cape Walsingham, lat. 66° 34', long. 60° 50', October 12th, natural 

 temperature 30°, density 1*0245. 



Slight as the differences in these densities may appear to be, in 

 my own estimation they are assignable to no other cause than the 

 increased saltuess of the water on the east shore, consequent upon 

 a tendency of the water to advance from the southward, and the 

 diminished salinity resulting from the dilution of the water moving 

 to the southward. The above cases taken by chance, I have cited 

 from the observations made every day at noon ; and, although the 

 results at Cape York and Cape Farewell do not bear out the im- 

 pression conveyed by the whole, we may still presume that impres- 

 sion to be safe in a general point of view. The exception at Cape 

 Farewell arises in all probability from a diversion of the great 

 Arctic Current which flows round that promontory, and carries 

 into that part of the Strait ice and drift-wood which may have 

 come southward from great distances in the Greenland Seas ; and 

 in this respect it may be taken as a proof of the dilution of the 

 water of that current consequent upon its burden of comparatively 

 freshwater ice. Again the exception at Cape York may arise from 

 some local cause, such as the presence of an unusually large number 

 of icebergs. On our own coasts the mean density of the sea is 

 often disturbed by the discharges of rivers and small streams. An 

 evening of rainy weather in November of the past year reduced 

 the density of the sea in Stromness harbour from 1 '0285 to 1 * 0235, 

 and eighteen hours of heavy rain on the I7th of the same month 

 reduced that of the water of St. Margaret's Hope, Frith of Forth, 



* On the causes which may have produced changes in the earth's superficial 

 temperature. By W. Hopkins, Esq., M.A., F.R.S., &c., Quart. Journ. Geol. 

 Soc. vol. viii., pp. 56 et seq. 



t Compare Forchhammer's Observations on the Currents and SaHnity of 

 the Polar Seas in the Reports and Transactions of the Bi-itish Association, 

 1846. 



