Correspondence — Rev. O. Fisher, 3o 



liarity attaches to it, that the last agency at work necessarily oblite- 

 rates the marks of others which may have preceded it. When, 

 therefore, we are discussing this subject, it is important to avoid 

 misconception by stating clearly what stage of the whole process we 

 are upon. One may say, we have marine action here ; another, we 

 have glacial ; another, pluvial. Each may be right if he limits his 

 assertion to the proper stage ; each will be in error if he carries it 

 beyond. It is as, in describing the fashioning of a board, we might 

 truly assert it to have been cut either by the axe, or by the saw, or 

 by the plane. But if we were to attribute the formation of the 

 smooth surface to one of the two former instruments, the assertion 

 would be incorrect. 



The present phase of the discussion refers, I apprehend, to the 

 final stage of denudation. To use the above illustration again, 

 were I shown a board, and asked by what tool the surface had been 

 brought to its present condition, I should look at two things — first 

 at the form of the surface, and, secondly, at the condition of it. From 

 the two together, I should be able to arrive at a sure judgment of 

 the mode by which the surface had been produced. Now, I think 

 that these tests have not been carefully enough applied to discover 

 the true cause of the form of the ground. The acknowledged power 

 of rain to carry some portions of the soil into the rivers, and the 

 power of rivers to convey what the rain gives them into the sea, 

 does not prove that the contour of our landscape was produced by 

 those agents. The question to be decided is, whether rains can mould 

 the surface to the particular form which it presents, and whether it 

 can remove, not some material, but the particular material of which 

 each locality has been denuded. This is a question concerning the 

 mechanical power of water, in the quantities which rain yields, 

 moving over surfaces having the minimum inclination of the denuded 

 country. And when we call in the assistance of the weather to dis- 

 integrate the harder rocks so as to fit them for removal by rain, we 

 must recollect that, in cases of unequal solubility, the harder por- 

 tions would be left, if only temporarily, to accumulate behind, and 

 thus to point out the manner in which the waste of the surface was 

 being effected. Neither must it be forgotten that such pluvial action 

 must have been carried on when all the less elevated parts of the 

 surface were covered with herbage, as they would have been if the 

 climate was not glacial. If it was glacial to the extent of preventing 

 the growth of herbage, then ice action would have taken place. 



The second index to the agency which has been in operation is to 

 be found in the condition of the surface. It is inexcusable to neglect 

 the study of this, which is to be seen in every shallow pit or ditch 

 that is opened. Such sections always afford an interesting study. 

 We must no longer be content to disguise our slothful ignorance of 

 the true nature of the first few feet of every section under such terms 

 as ''heading," "vegetable soil," "rain wash" (unless we can ^rove 

 it such), "rubbish," or what not. There you have a veritable re- 

 cord of the last touch of Nature's hand in fashioning the landscape. 

 Say, what tool did She use ? Those contorted layers of gravel, those 



