•;oo 



PHYSIOGRAPHY. [chap. 



Thames basin ; but there would be nothing new in the 

 general truths exemplified by the study of these additional 

 facts. 



Whatever direction the journey of the traveller from 

 London might take, he would, sooner or later, reach sea- 

 water, which, whatever its local name, is really a dependence 

 of the Atlantic Ocean ; and he would, thereby, convince 

 himself that the land of Great Britain constitutes what 

 geographers term an island. Indeed, it is an island of no 

 great magnitude ; for there is no point of its surface from 

 which the sea coast may not be reached, by three days' good 

 walking. 



Of a roughly triangular form, it measures about 600 miles 

 from south to north, by about 320 miles from east to west, 

 at its broadest part; and its superficial area amounts to 

 89,644 miles. In other words, its superficial area is nearly 

 equal to that of a square, 300 miles in the side (300 x 300 

 = 90,000). There is no subject respecting which people 

 have more vague ideas, than in regard to the relative areas 

 of the dififerent parts of the earth's surface ; and it will be 

 useful, in considering other parts of the world, to take the 

 area of the British islands as a unit of superficial measure- 

 ment, represented by the Roman numeral I. Thus I. will 

 represent 90,000 square miles; II. 180,000; \ 45,000, and 

 so on. 



Separated from Britain on the west, by a sea which is 

 not more than thirteen miles wide, where it is narrowest 

 (between Fair-head and the Mull of Cantire) is another 

 island of considerable size, that of Ireland. This island 

 measures 300 miles from north to south, by 180 miles, from 

 east to west, and has an area of 32,513 square miles (^). 

 Moreover, fringing the west coast of Britain, especially in 

 its northern part, and extending beyond its northern end, 



