378 ON THE NATUEE AND ORIGIN OF 



force of a giant pump. But where the head and power 

 for such a siphon tube is from fifty to one hundred and 

 forty miles away from the watershed over which the debris 

 is to be lifted, the chances for a perfectly tight tube of that 

 length are exceedingly slender. Such phenomena have never 

 been seen. 



Impossible Theories. — I think the evidence justifies one 

 in saying that siphon-like action by subglacial streams on 

 such a large scale is absolutely impossible. I will consider 

 further objections to this theory later on. 



Superglacial Streams. — The theory of superglacial streams 

 as a source of esker formation is also untenable because 

 Nansen and other explorers say that glaciers or smooth or 

 slightly undulating slopes carry no debris on their surface, 

 as to those glaciers lying among projecting mountains 

 According to Nansen, Peary, Nordenskjold, Shackleton, 

 Amunsden and other explorers, neither Greenland nor the 

 Antarctic continent show any support for the theory of the 

 formation of eskers by either subglacial or superglacial 

 streams. 



Confused Theories. — To show the confusion and uncertainty 

 attending past investigations into the origin of eskers, I 

 will give several quotations showing the indefinite and 

 contradictor}^ theories so f ar advanced. On page 422 Stone 

 says: "The conclusion is that the great length of the eskers 

 of Maine favor s the hypothesis that they were mainly 

 formed in subglacial tunnels", yet on page 426 he says, "So 

 far the probabilities favor the theory of superficial streams." 



On page 363 both theories are reduced to impotence 

 when we read this: "We naturally wonder whence the gravel- 

 moving waters came and whither they went and what became 

 of the finer material they carried with them". So the mystery 

 deepens, and deeper mystery follows when we ask where 



