1865.] Pengelly on the Causes of Britain's Greatness. 33 



fited by it both directly and indirectly ; directly, by the warmth 

 which it brings us, which, according to Mr. Hopkins, raises the tem- 

 perature of Snowdon (taken as representing the mean of England) by 

 fifteen degrees of Fahrenheit during the month of January, and our 

 mean annual temperature by half as much ; indirectly, by strangling 

 at the beach the glaciers formed in the valleys of Spitzbergen, and 

 which were about to start, as icebergs, to chill the waters washing our 

 northern coasts. Here, then, is a cause for the great northward de- 

 flection of the isotherms traversing the north-eastern portion of the 

 Atlantic, and to it may be added the fact that Europe, of the three 

 great northern divisions of the earth, extends least into the frigid 

 polar regions. The lower temperature of the Atlantic sea-bord of 

 North America is due to more than the negative fact that it is not 

 visited by any body of heated water ; it is mainly attributable to a 

 current moving southwards from Baffin's Bay, which not only consists 

 of water of low temperature due to its arctic origin, but transports 

 vast fleets of icebergs. Sir John Boss saw several of them in Baffin's 

 Bay, aground in water 1,500 feet deep ; that is, fully five times deeper 

 than the English Channel, even between Brest and the Land's End. 

 It is stated by Sir Charles Lyell that the thawing of icebergs, as they 

 drift southward, has been known to cool the water sensibly for fifty 

 miles around, and sometimes as much as eighteen degrees in their 

 immediate neighbourhood. Occasionally a large number are stranded 

 on the west coast of Iceland, where they cause a failure of the crops 

 by the fogs they incessantly generate, and drive the fish from the 

 coasts by the reduction of the temperature of the water. 



The British islands are, on the whole, well supplied with harbours 

 and roadsteads. Should the era of large merchantmen, predicted by 

 the ' Great Eastern,' ever be realized, the safe and capacious Milford 

 Haven will be found to occupy a prominent place in the history of 

 our commercial marine. 



None of our numerous rivers, of dimensions available for inland 

 navigation, are obstructed by rapids or waterfalls ; it is scarcely pos- 

 sible, however, to study the gorges through which some of them pass 

 without being convinced that, in fierce and long-continued conflict 

 with the rocks which bound them, they have w r on the channels they 

 occupy. We are taken back to a remotely distant time when some of 

 our streams fell helplessly over opposing ledges ; we see the fall 

 slowly dwindle into a rapid, and this in its turn give place to a river 

 of tranquil flow. 



How much, also, do we owe to our vast and varied mineral wealth ! 

 The metals of Britain influenced history before the dawn of modern 

 civilization. The adventurous and enterprising spirit which led the 

 early Phoenician to Cornwall in quest of the tin it contained, was no 

 doubt thereby fostered and developed, as well as transfused into the 

 ancient Cornubii. Our mineral produce in 1862 was worth more than 

 thirty-four and a half millions sterling ; of this vast sum the value of 

 the coals was considerably over twenty millions, and of the iron 

 nearly ten millions. It has been said that " iron is the backbone of 

 nineteenth-century civilization ;" it may be added that coal is th® 



VOL. II. I) 



