784 THE POPULAR SCIENCE MONTHLY. 



bowlders, forming the terminal moraine of the ice-sheet. This is 

 exactly similar in general form and structure to the moraines left 

 by the old Alpine or North British glaciers, and if the former 

 could have been produced by a flood so could the latter. But the 

 American terminal moraine runs across the country almost irre- 

 spective of its contour, and is often as well marked on plateaus as 

 in valleys and on the intermediate slopes. Moreover, this moraine 

 often lies on the southern slope of the hills draining toward the 

 Mississippi Valley ; and we are asked to believe that a flood vast 

 enough to carry gravel and rocks for hundreds of miles to such a 

 position, left them all stranded on a slope down which it must 

 have been rushing with increased velocity and without hindrance 

 toward the Gulf of Mexico ! So far as I know, Sir Henry Ho- 

 worth is absolutely alone among living writers in his diluvial 

 theories, and I only give this brief statement of their over- 

 whelming impossibilities because his book is so interesting, and 

 his assertions that his theory explains all the facts are so con- 

 fident and so often repeated that they are likely to confuse the 

 judgment of readers who have not paid special attention to the 

 subject. 



Returning to the main question, of the possibility of glaciers 

 or ice-sheets moving over long distances of generally level ground 

 with intervening hills and valleys, there is an important piece of 

 evidence, the bearing of which appears to have been overlooked 

 by objectors. The former existence of the great Rhone glacier 

 carrying erratics to the slopes of the Jura from beyond Geneva 

 on the southwest to Soleure on the northeast, is universally ad- 

 mitted. This glacier passed out of the gorge between the Dent 

 du Midi and the Dent de Morcles, and a little below St. Maurice 

 enters on the alluvial plain which extends to the lake. From this 

 point to Geneva, a distance of about sixty miles, may be consid- 

 ered a level plain, the descent into the lake being balanced by the 

 ascent out of it. Yet it is admitted that the glacier did move 

 over this distance, since erratics which can be traced to their 

 source on the left of the valley below Martigny are found near 

 that city. But the main part of the glacier curved round to the 

 right across the Lake of Neufchatel, and extended at least as far 

 as Soleure, a distance of about ninety miles. To do this it must 

 have ascended five or six hundred feet to the country around 

 Fribourg, and before reaching Soleure must have passed over a 

 hill three or four hundred feet higher. Yet on the flanks of the 

 Jura above Soleure there are erratics which have been carried on 

 the surface of the glacier from the east side of the valley below 

 Martigny, and close to Soleure itself there are remains of a ter- 

 minal subglacial moraine of compact bowlder clay. Sir Charles 

 Lyell describes this as 



