THEIR VARIABLE DIRECTION'. 
•2ft 
amidst the rigours of winter in the temperate zone, more 
nan 3 or 4* degrees of the temperature it had under the 
tropies. The greatness of the mass, and the small eonduct- 
Tr +i °^, wa * :cr * or heat, prevent a more speedy refrigeration, 
it, therefore, the Gulf-stream lias dug a channel at the bottom 
ot the Atlantic ocean, and if its waters are in motion to 
considerable depths, they must also in their inferior strata 
keep ivp a lower temperature than that observed in the same 
parallel, in a part ot the sea which has neither currents nor 
deep shoals. These questions can be cleared up only by 
direct experiments, made by thermomctrical soundings. 
Sir Erasmus Gower remarks, that, in the passage from 
England to the Canary islands, the current, which carries 
vessels towards the south-east, begins at the 39th degree of 
latitude. During our voyage from Corunna to the coast of 
couth America, the effect of this motion of the waters was 
perceived farther north. Eroni the 37th to the 30th degree, 
ie deviation was very unequal ; the daily average effect 
vas 12 miles, that is, our sloop drove towards the east 75 
miles in six days. In crossing the parallel of the straits of 
Gibraltar, at a distance of 140 leagues, we had occasion 
o observe, that in those latitudes the maximum of tm; 
rapidity does not correspond with the mouth of the straits, 
. "ith a more northerly point, which lies on the prolonga- 
tion of a line passing through the strait and Cape St. Vin- 
cent. This line is parallel to the direction which the waters 
oilow from the Azores to Cape Cantin. We should more- 
over observe (and this fact is not uninteresting to those 
who examine the nature of fluids), that in this part of the 
retrograde current, on a breadth of 120 or 1 40 leagues, the 
v hole mass of water lias not the same rapidity, nor does it 
oilow precisely the same direction. 'When the sea is per- 
ectly calm, there appears at the surface narrow stripes, like 
small rivulets, in which the waters run with a murmur very 
sensible to the ear of an experienced pilot. On the 13tb 
?, June, in 34° 3G' north latitude, we found ourselves in 
. le Midst of a great number of these beds of currents. We 
ook then 1 direction with the compass ; and some ran nortli- 
east, others east-norilveast, though the general movement 
0 the ocean, indicated by comparing tlic reckoning with the 
chronometrical longitude, continued to he south-east. It 
