ANNIVERSARY ADDRESS. 13 



The following extract is worth notice : — " The heat-giving pro- 

 perties of the Equatorial and north-east Trade current, carrying 

 as they do, a continuous body of warmed water towards the 

 Caribbean Sea can be traced by rise of temperature of the whole 

 body of water at Sombrero, and afterwards to all the stations on 

 the North Atlantic, but most readily so by the widening of the 

 Isotherms, about 62° F. between America and the Azores, forming 

 an immense reservoir of warmed water 1,000 feet thick, and at 

 least 2,000,000 of square miles in extent. This change of tem- 

 perature or disturbance is greater and nearer to the surface on 

 the western side of the Atlantic, the nearest point to the source 

 of the current than at the eastern side, where it slowly but 

 gradually expands itself, sinking as it expires." 



The Gulf Stream being only superficial, extends 100 fathoms 

 down, and underneath it is the cold Labrador current running 

 southward on the American coast ; but the Equatorial stratum 

 of warm water expands an enormous store of heat 3,250 miles 

 from the Gulf Stream, retaining a steady temperature, and 

 stretching to the coasts of Europe north of the Azores. The 

 same warm stratum extends from 2G0 miles north of St. Thomas's 

 to the Gulf Stream, a distance of 1,000 miles. The origin of this 

 immense body of warm w r ater is not yet known. It is no doubt 

 the cause of the moderate temperature of the south and south- 

 west coast of England and the West of Ireland, just as our 

 Sydney winters are milder from the influence of the Pacific Stream 

 from the north-east. It is said that the Gulf Stream may be 

 traced to Spitzbergen. 



In his Eeport of 15th September, Captain Nares mentions that 

 at Porto Eayo, in Saint Jago, one of the Cape Verde Islands, a 

 red coral similar to that in the Mediterranean was found growing 

 at 80 fathoms of water at 52° of temperature, which is that of 

 the Mediterranean banks, and he adds, ""We have never found 

 that temperature at the same depth further north." 



In the year 181G, a paper of mine on the island of Lafu was 

 read before the Geological Society of London (Q.J.G.S. Ill, 63)? 

 in which I mentioned the fact that certain corals grew in Port 



