310 On the Fall oj Rivers. 



of the Tweed being 96-4 miles, and its total fall 1500 feet ; 

 the length of the Clyde 98 miles, with 1400 feet of fall. In- 

 deed both rivers for many miles from their source flow nearly 

 in one direction, never diverging to any great distance from 

 each other ; and so long as they continue nearly parallel, 

 they flow almost upon the same level, and keep on a high 

 table-land of country, as if hesitating whether to mingle their 

 waters or to remain separate, and whether to turn their 

 courses to the eastern or western slope. Thus they pursue 

 their sympathetic career till near Biggar, when they termi- 

 nate their upper course, and like two wanderers descending 

 from the mountains together, and separating by cross-roads 

 when they have reached the low country, they at last part, 

 the one turning eastward and the other westward. At this 

 spot the rivers are only 6^ miles distant from each other — 

 are on the same level, and have the same distance to travel 

 ere they reach the sea — yet what a difference in their de- 

 scent ; the Tweed pursues its course evenly and gently ; 

 while the Clyde has not parted from its former companion 

 for a greater distance than 18 miles, before it boldly dashes 

 over a whole series of those well-known falls, the principal 

 of which are the Bonnington and Stonebyi*es Fall, and Corra 

 Linn. The descent over all these falls is computed at 230 

 feet.* 



Thus the preceding examples sufficiently attest that the 

 occurrence of cataracts and other sudden descents in a river 

 depends but little on its aggregate fall. 



Thus there is certainly " room in the Jordan for thi-ee cata- 

 racts, each equal in height to the Niagara," as Professor Ro- 

 binson remarks ; but, on the other hand, if there should not 

 be discovered one single rapid in it, there is still nothing of 

 a remarkable phenomenon about it. 



The different points on the subject thus adduced are reca- 

 pitulated as folh'ws : — 



1*/, Lieutenant Syrnonds' results for the depression of the 

 Dead Sea (1312 feet), compared with the different barome- 

 trical results, do not prove such an amount of discrepancy as 

 to justify a doubt in their accuracy. 



* FuUarton's Parliamentary Gazetteer of Scotland, vol. i., p. 232. 



