294 Prof. A. C. Ramsay on the Erosion 



any man of weight and knowledge could be found to follow me 

 at all. I may therefore be pardoned if in this instance I depart 

 from the course of leaving the value of my theory to be worked 

 out solely by time. 



I have said that Sir Roderick has entered an authoritative 

 protest, because, as several persons have remarked to me, so much 

 stress has been laid on the argumentum ad hominem, liberally as 

 regards Continental geologists, and more sparingly with Ame- 

 rican and English names. Indeed, in reading the Address, I 

 was more than once reminded of the observation of one of my 

 opponents, who in the ' Reader ' observed to this effect, " that 

 Professor Desor entirely disagrees with Professor Ramsay — how 

 can he do otherwise ? for Desor has lived among glaciers all his 

 life." In like manner Studer and Escher von der Linth, " by 

 numerous appeals to nature," Gastaldi, De Mortillet, and many 

 more are all arrayed in opposition to the theory, the presumption 

 being that the chances are therefore infinitely against it, and I 

 must needs be wrong because they are so eminent, and some of 

 them have lived so long among the Alps. For, differing from 

 them, how is it likely that a man can be right who has only ex- 

 plored the Alps five or six times with a special objc ct, even though 

 he may have spent^five-and-twenty years on subjects allied to or 

 identical with it ? Such is the general impression produced, not 

 on myself alone, by many of Sir Roderick's remarks. I have no 

 objection to this kind of argument ; it is so old in the history 

 of science that its value is understood. To compare great things 

 with our small matter, Copernicus and Galileo experienced it, 

 Hutton and Playfair knew it well ; the most eminent geologists 

 were for long deaf to the voice of William Smith, let him charm 

 ever so wisely; and Agassiz himself, in glacial geology, had 

 among his chief opponents distinguished seniors, some of whom 

 even now only hesitatingly follow him. It is easy to " appeal to 

 nature," but the language of her reply is not always to be 

 understood merely by long poring on her face ; and it generally 

 happens that many an abortive effort is made before some happy 

 accident reveals the key. 



In my original memoir, when discussing the origin of the lake- 

 basins, I found it necessary in some degree to treat of disturb- 

 ances of rocks in general. Accordingly, Sir Roderick very pro- 

 perly regards the question as one not merely of lakes, but as 

 involving his belief "with the vast majority of practical geologists, 

 that the irregularities of the surface of the Alps havebeen primarily 

 caused by dislocations and denudations;" and again, that "until 

 lately geologists seemed so be generally agreed that most of the 

 numerous deep openings and depressions which exist in all lofty 

 mountains were primarily due to cracks which took place during 



