CLIMATE. 



17 



The largest of these is Lough Neagh, which covers an area of 156 square miles, 

 whilst Loch Lomond, the most extensive Highland lake, only spreads over 45. 

 But size is not beauty, and few of the lakes of Ireland can compare with 

 those of the Highlands and the Cumbrian hills in their picturesque surroundings. 

 Yet even the largest of the Irish lakes is insignificant if we contrast it with the 

 vast sheets of fresh water met with in other countries, more especially in î^orth 

 America. 



A line drawn through Great Britain to mark the water-parting between the rivers 

 which empty into the German Ocean and those flowing towards the west will be 

 found to divide the island into two unequal portions, the larger of which lies to the 

 east. Nearly all the great rivers flow in that direction, the Severn forming 

 the only notable exception. In Ireland, on the other hand, the drainage is prin- 

 cipally to the westward and southward, the Boyne being the only river of any 

 importance which flows into the Irish Sea.* 



Climate. 



Gre.\t are the advantages which the British Isles derive from the mildness and 

 equability of their climate. Washed by the tepid waters which move slowly from 

 the tropical seas towards the Arctic Ocean, they form part of the domain of the 

 Atlantic, whose humid atmosphere envelops them. Nowhere else in the world, 

 except in the Faroe Isles and on the western coast of Norway, does the actual 

 temperature differ to the same extent from the temperature which might be looked 

 for from the geographical position of the country with reference to the equator. 

 In no other instance do the isothermal lines sweep so far to the northward. The 

 mean annual temperature of Ireland, under lat. 52° N., is the same as that of the 

 eastern coast of America, 980 miles farther south, under lat. 38°, and the winters 

 in the extreme north of Scotland are as mild as in the New World, 20° of latitude 

 nearer to the equator. 



* The principal river basins of the British Islands, including all those having an area of over 1,000 

 square miles : — 



Area in Length 



Sq. Miles, in Males. 

 Great Britaix : Eastern Watershed. 



Spey 1,190 96 \ 



Dee of Aberdeen 765 87 



Tay 2,250 107 



Forth 645 60 



Tweed 1,870 96 



Tyne 1,083 73 



Humber 9,293 204 



Trent 4,0-52 167 



Ouse 4,207 131 



Witham 1,050 89 



Nen 1,055 99 



Great Ouse . 2,766 156 



Yare and Waveney 1,210 81 



Thames and Medway . . . . 5,935 215 



Great Britain : Sol'thern Watershed. 



Avon of Salisbury 1,132 67 



108 



Area in Length 



Sq. Miles, in Miles. 



Great Britain : Western AVatershed. 



Severn 8,119 186 



Severn proper 4,350 158 



Avon of Bristol .... 891 62 



Wye . 1,609 135 



Usk 540 65 



Mersey 1,722 85 



Eden 995 69 



Clyde 1,580 98 



Ireland. 



Boyne 1,040 70 



Earrow, Suir, and Nore . . . 3,555 119 



Blackwater 1,284 104 



Shannon 6,060 225 



Corrib 1,212 64 



Erne 1,689 64 



Foyle 1,129 73 



Bann 2,242 85 



