58 Lincolnshire Notes & Queries. 



sedimentary strata of varying resistance. In the course of 

 this development the land has been, at least once, worn down 

 to a lowland of faint relief, and afterwards broadly uplifted, 

 thus opening a second cycle of denudation, and reviving the 

 rivers to new activity ; and, in the second cycle of denudation, 

 the adjustment of streams to structures has been carried to a 

 higher degree of perfection than it could have reached in the 

 first cycle." He then goes on to differ with previous authors 

 and workers on the subject Ramsay, Greenwood, Foster, 

 Topley, Whittaker, Green, Jukes-Browne, and others in the 

 fact of their starting the drainage of rivers on planes of 

 "marine erosion," whereas he urges that rivers, and sub-aerial 

 forces, account for it all. By such latter agencies, he thinks, 

 and thinks rightly, that land surfaces, hard and soft alike, may in 

 time be reduced almost to a level a "peneplain" as he terms it. 

 You will have noticed in his thesis that he speaks of the 

 land, after being worn down to a lowland of faint relief, being 

 broadly uplifted again, "thus opening a second cycle of 

 denudation, and reviving the rivers to new activity." The 

 features of this second cycle, he points out, will differ in two 

 significant respects from those of the first. There would be, 

 in the first place, at the beginning of the initial cycle, no 

 subsequent streams, all the drainage would be trans^perse^ or 

 consequent as he terms it. At the beginning of the second 

 cycle the greater part of the drainage would be revived along 

 the subsequent streams left by the first cycle at the end of its 

 career ; and, with this gain to start with, the adjustmentS'of 

 the second cycle would naturally exceed those of the first. 

 Then, in the second place, the escarpments, or ridges, left by 

 the first cycle would, for some time, retain the even form they 

 were reduced to at the close of that cycle ; and, when these 

 two special features occur together in a region, it can, he says, 

 "hardly be doubted that two cycles of sub-aerial denudation 

 have been, more or less, completely passed through in its 

 geographical development." He then goes on to show that 

 this theory is pertinent to the development of the newer rivers 

 of England ; for everything, as he says, points to the former 

 higher stand, and greater mass, of the land in the west in the 

 first instance ; then to the consequent or transverse streams that 

 flowed from this high land to the eastern sea ; then to the 

 development of subsequent streams along the weaker strata, and 

 the diverting and tapping of the primary transverse courses as 

 a necessary sequence. 



