SUKFACE WATERS OF THE NORTH ATLANTIC OCEAN. 
81 
Newfoundland and the Gulf of St. Lawrence, and appi'oaching the coast between 
Nantucket Island and New York. Temperature falls quickly on the land side of the 
5° line, especially to S.E. of Newfoundland. The isothermal of 7° fits into the loop of 
the 10° line when the latter follows the 50th parallel, i.e., east of long. 40"^ W. ; it indi¬ 
cates that the temperature gradient is turned southward rather than south-eastward. 
On the eastern side, clear of the land, the distribution of temperature is extremely 
uniform, TemjDerature falls from 15° to 10° in 15° of latitude ; the position of the 9° 
line is ill-defined. The lines of 7° and 8°, however, indicate that the fall becomes 
more rapid to north and west of the Faeroe Islands. The Faeroe-Shetland Channel 
is marked by an axis of over 7°, and a similar axis extends into the North Sea between 
Scotland and the Shetlands. 
The distribution of salinity shows the same general features as that of temperature. 
On the western side the line of 35 mille closely agrees with the 10° isothermal iii 
defining the northern border of the Gulf Stream, while the line of 3G pro mille agrees 
with that of 15°. On the eastern side the 36 pro mille line again agrees with the 
15° isothermal, hut the salinity remains about 35 over the whole area covered by 
tlie observations up to the Faeroe Islands. The head of the 10° line and the position 
of that of 7° in mid-ocean are reflected in the form of the line of 35'4 pro mille 
Salinity, and again in tlie detached part of the 35 line running east from lat. 50° N. 
long. 40° W. The hand of low temperature I'unning S.F. from the Newfoundland 
Banks is represented, hut in a much more marked degree, by water of low salinity ; 
there is a steep gradient from 35'0 to 30'0 on both sides, and water of 34'0 extends 
down to lat. 40° N., and apparently spreads westwai'd along the southern L'order 
of tlie Gulf Stream. 
I'hus we have In lat. 40° N. two surfaces of almost eipially warm and salt water, 
one on each side of the Atlantic. One—the Gulf Stream water—stops off the 
land near the deep water line to the south of the Gulf of St. Lawrence ; the other 
extends northwards along the coast of Europe, as for as the observations go, in a 
steadily narrowing tongue, and westwards to about long. 40° W. These tv/o surfaces 
are entirely separated, down to 40° N., by a band of fresher colder water, stretching 
S.E. from the Newfoundland Banks. 
Fehruary, 1S9G.—The observations for this month are increased by a line to 
Reykjavik. 
In the lower latitudes the isothermal of 15° now follows the ^larallel of 40° N., 
exce})t between about 12° and 22° W. long., when it bends slightly southward, and 
between 40° and 45° W., where there is a t\nn northward. The line of 5° has 
moved southward, hut retains practically the same shape as in January. Temperature 
gradients have thus become much steeper west of 40° W. long. In mid-Atlantic the 
distribution of temperature .shows little change, hut in the eastern part of the ocean 
there is a tendency to equalisation; the water is slightly colder off the coast of 
Portugal, and apparently warmer between Faeroe and Icelaiid, the line of 8° liaving 
VOL. cxcvi.-- A. :\r 
