Chemistry and Physics. 225 
regions is perfectly obvious. The surface-water at the equator is 
swept into the Gulf of Mexico by the trade winds and the equato- 
rial current, as rapidly as it is heated by the sun, so that it has 
not time to gather to any great depth. But all this warm water 
is carried by the Gulf-stream into the North Atlantic, where it 
accumulates. That this great depth of warm water in the North 
Atlantic, represented in the section, is derived from the Gulf- 
stream, and not from a direct flow from the equator due to gravi- 
tation, is further evident from the fact that temperature sounding 
A in latitude 38° N. is made through that immense body of warm 
water, upwards of 300 fathoms thick, extending from Bermuda to 
near the Azores, discovered by the Challenger Expedition, and 
justly regarded by Captain Nares as an offshoot of the Gulf 
r 
ermuda and the Azores; sounding 5 is No. 
6 “temperature curve,” between Teneriffe aud St. Thomas. 
There is an additional reason to the one already stated why the 
surface temperature of the South Atlantic should be so much 
rent. But, according to the gravitation theory, the colder water 
should be adeeciak. ie © 
1 fact of a mass of water, 200 fathoms deep and ex- 
tending over fifteen degrees of latitude, remaining above water of 
or four degrees higher temperature, shows how little influ- 
ence difference of temperature has in producing motion. 
ad the potency which some attribute to it, one would suppose 
isplace the warm 
water underneath. If difference of density is sufficient to move 
the water horizontally, surely it must be more than sufficient to 
Te a sink vertically. Scie les 
- On the artificial imitation of magnetipolar native platinum ; 
by M. oe og a memoir read before the 
* Captain Nares’s Report, July 30, 1874. 
Am. Jour. Scr. Tarrp seers ae X, No. 57.—Supr., 1875. 
