in the Vorarlberg, in the Aulu?nn of 1846. 239 



autumnal months, after the usual rains at that period. Some 

 solid matter is washed into the current, and deposited some- 

 where at a lower level ; and as this takes place on every 

 stream in every part of the earth's surface, we are assured, 

 that should the same causes be permitted to act during a 

 sufficiently long period, the time will certainly arrive when 

 the ocean shall ovei»flow the present dry land, its own basin 

 having been filled up with the debris.* 



The effects produced are not always of the gradual charac- 

 ter now referred to. Sometimes large masses of the banks 

 are quickly overwhelmed and carried down the stream. The 

 materials are removed to no very great distance ; but still 

 their position has been changed, and the loss of cohesion en- 

 ables the water to remove them much farther than would at 

 first have been supposed. Many such occurrences have been 

 recorded in the annals of past times, and many more have 

 been described in recent periods, since the attention of men has 

 been called to such things. When a bridge is overturned by 

 the force of the current, part of the materials are carried 

 down the stream to a great distance. When a river leaves 

 its accustomed channel, and cuts out a new one for itself, the 

 solid matter which formerly occupied the place now held by 

 water, has been carried down far from its former site.f We 

 cannot read many pages of such a work as Sir Thomas Dick 

 Lauder's Account of the Morayshire Floods, without seeing 

 ample proof of the power of running water to remove to a 

 great distance even stones. Of large size, of course, rounded 



* The causes which are now elevating the land in several districts are local 

 and variable. The action of running water is universal and unceasing. 



t Mr Lyell says,— " The power of even a small rivulet, when swollen by 

 rain, in removing heavy bodies, was lately exemplified in the College, a small 

 stream which flows at a moderate declivity from the eastern water-shed of the 

 Cheviot Hills. Several thousand tons weight of gravel and sand were trans- 

 ported to the plain of the Till, and a bridge tlien in progress of building w&a 

 carried away, some of the archstones of which, weighing from half to three- 

 fourths of a ton, were propelled two miles down the rivulet. On the same oc- 

 casion the current tore away from the abutment of a mill-dam a large block of 

 greenstone porphyry, weighing nearly two tons, and transported it to the dis- 

 tance of nearly a quarter of a mile." This was in 1829. — Principles of Geology, 

 vol. i., p. 254. 



