300 On the Influence of the Gulf Stream, 



Mr. Kedfield^ states, that in 1831 the harbour of St. John's, New- 

 foundland, was closed with ice as late as the month of June ; yet 

 who ever heard of the port of Liverpool, on our side, though 2° 

 farther north, being closed with ice, even in the depth of Winter ? 

 (Maury.) 



Again, in Baffin's Bay, on the west coast of Greenland, the glaciers 

 stretch out from the shore, and furnish repeated crops of mountainous 

 masses of ice which float off into the ocean.^ The number and 

 dimensions of these bergs is prodigious. Captain Sir John Koss saw 

 several of them together in Baffin's Bay aground in water 1,500 feet 

 deep! Many of them are driven down into Hudson's Baj'', and 

 accumulating there, diffuse excessive cold over the neighbouring 

 continent ; so that Captain Franklin reports, that at the mouth of 

 Hayes' Eiver, which lies in the same latitude as the north of Prussia 

 or the south of Scotland, ice is found everywhere in digging wells, 

 in summer, at the depth of four feet ! ^ 



How comes it that there is this great disparity in the relative 

 temperature of places lying in tlie same parallels of latitude ? The 

 explanation is to be found in the prevalence of certain winds and 

 oceanic currents, which cause the isothermal line of 32° F- to vary 

 as much as 14° of latitude in passing from east to west, as shown by 

 Professor Dove.* 



By far the most important of oceanic currents to us is the Gulf 

 Stream. It is, says Captain Maury,^ " a river in the ocean : in the 

 severest droughts it never fails, and in the mightiest floods it never 

 overflows ; its banks and its bottom are of cold water, while its 

 current is of warm ; it takes its rise in the Gulf of Mexico, and 

 empties into Arctic seas. There is in the world no other such 

 majestic flow of waters. Its current is more rapid than the Missis- 

 sippi or the Amazon, and its volume more than a thousand times 

 greater. Its waters, as far out from the Gulf as the Carolina coasts, 

 are of indigo blue. They are so distinctly marked that their line of 

 juncture with the common sea-water may be traced by the eye. 

 Often one half of the vessel may be perceived floating in Gulf- 

 stream-water while the other half is in common water of the sea, — 

 so sharp is the line, and such the want of affinity between those 

 waters, and such, too, the reluctance, so to speak, on the part of 

 those of the Gulf-stream to mingle with the littoral waters of the 

 sea." 



This stream is about 25 miles in breadth off Cape Florida, whence 

 its width increases to 127 miles off Sandy Hook, whilst its depth 

 diminishes from 1000 feet to 200 and under as it proceeds north- 

 wards. 



From the American coast and ihe banks of Newfoundland it is 

 diverted across the Atlantic, reaching the Azores in about 78 days, 



* Silliman's American Journal of Science, vol. xiv. p. 293. 



* Scoresby's Arctic Regions, vol. i., p. 208. 



' Lyell's Principles, 10th edition, vol. i., chap, xii., p. 245. 



* Lvell's Principles, vol. i., p. 239, 



* Physical Geography and Meteorology of the Sea, 8th edition, 1860, p. 23. 



