THE GULF STEEAM. 4l5 



to the American coast, beyond the usual limits of where the division lies in 

 other Oceans between the Westward tendency of sea and air within the 

 Tropics, and the Eastward movements of extra-Tropical latitudes. Hence- 

 forth it leaves the coast on a due Eastward course to the South of the 

 great collection of banks which lie off the British American possessions, 

 and this portion of the Stream will be considered in the following pages. 



(408.) Eastern Extension between about 68"^ and 48^ W. — In examining 

 the condition of the Gulf Stream, in the next 850 miles, we encounter 

 many difficulties. Its physical features, the interferences it encounters, 

 the opposing streams which neutralize its onward course, and the ever- 

 varying rate of its current, have all to be taken into consideration. By 

 confining the observations to those made, in the summer season, by the 

 United States officers, off Nantucket, and to the current observations 

 integrated by the Meteorological Office, it might almost be inferred that 

 the Gulf Stream ceased between Nantucket and the S.W. part of Nova 

 Scotia; for while the first makes the whole bulk of its warmer water to lie 

 South of lat. 38° hereabout, the current observations show no Eastward 

 drift to the Northward of that parallel in the same region. But the vary- 

 ing Easterly drifts, and the generally much warmer water which is found 

 than is due to the latitude, will point to its origin. By the rapid transport 

 of heated water into these regions by its Northern course, one feature is 

 brought into existence which has not been sufficiently considered — that of 

 the Fogs which characterizes the whole section now to be discussed. The 

 Nova Scotia and Nantucket Banks, as well as the Newfoundland Great 

 Bank, are proverbially regions of dense mist. The cool winds condense 

 the evaporation from the warm Gulf Stream waters over thousands of 

 square miles ; and this process, as well known, is one of the most effective 

 methods of cooling that can be imagined. 



In addition, therefore, to the inter-mixture of an enormous bulk of cold 

 Arctic water* in this part of its course, it has the no less active atmo- 

 spheric agents at work on its surface in bringing down its waters to less 

 than the normal temperature due to the latitude. The area, always more 

 or less enveloped in fogs, and densely so when the prevalent N.W. winds 

 blow, is not less than 20,000 square geographic miles in the offing between 

 Nantucket and the Grand Banks, and this is leaving out of the reckoning 

 all the other areas subject to the same chilling influences. 



H.M.S. Challenger, in her deep-sea exploring expedition, twice crossed 

 the course of the Gulf Stream in its Eastern portion ; the late Sir Wyville 

 Thomson remarked that where they crossed it, about 250 miles Eastward 

 of the Chesapeake, the Stream was 60 miles in width and 100 fathoms 

 deep. We presume that he considered the Stream had a river-like 

 appearance to this extent. 



» Commander W. Chimmo, E.N., in 1868, found that the Arctic Current swept the 

 rocky bottom bare on the Grand Bank and on the Flemish Cap, at the depth of 250 

 fathoms. He also found that the under-stratum of cold water was universal, and 

 that the Gulf Stream was very superficial ; thus, in lat. 44° 3' N., long. 48' 7' W., wbioh 

 would be in the main strength of the Stream, while the surface temperature was f^\ "• 

 at 50 fathoms it was 43°, or 18° polder, and this in July. See Proceedings of the Koyai 

 Geographical Society, vol. xiii. 



