308 TTNEDALE ESCAEPMEXTS ! 



Woodcut No. 6.— Transverse section of Druid stone, near Swinburne Castle, at about 

 oue and a half feet from the summit. The dotted lines indicate the original outline, al- 

 lowing nothing for disintegration of outer points, Scale one inch to one foot. 



"Woodcut No. 5 represents a section of this stone about eighteen 

 inclies from the summit, and shews the deep ruts made in the 

 original quadrate form indicated for us lower down. The modus 

 operandi which waste has taken will be described in another 

 page. For the meantime, disintegration grain by grain, is suffi- 

 ciently signallized by its effects within the human period upon 

 this scarred *' Druid" stone. 



Suitahleness of the Atmospheric Theory.— If, then, the wasting 

 influences of the atmosphere are not inadequate to the develop- 

 ing of hard nbs of rock into escarpments, wlien time upon a geo- 

 logical scale is allowed, it is obvious that none of the objections 

 found to weigh so heavily against the theories passed in reWew, 

 have any prejudicial bcaiing on the atmospheric one. Shed 

 broad-cast over the surface, these influences tend to pick out a 

 configuration solely determined by tlie natui'e of the materials 

 and the facilities for transport. 



Development of the Theory. — As late as 1861 the Crag-and-Tnil 

 of Edinburgh was referred by an accomplished geologist "to 

 some process not easily explained."* The late Beete Jukes, 

 among the later school of geologists, seems to have first ex- 

 pressed, in the following year, the principles of the pliilosophical 

 view BO long before taken by Uutton and Plajrfair.t In 186i3 and 

 1864 Professor Ramsay gave a remarkable digest of observations 



• Prof. Oelklo. Oeol. of Edinburgh. Mem. Oool. 8ur%-., p. 127. Cint ii«(ji'u, in 18A3. 

 had verged very closely u|>on the ntmo.ipherlc theory In his "Treellfter," p. 1S7. 

 t Quart. Jour. Gcol. 8oc.. Vol. .Will. 



