620 KANSAS CITY REVIEW OF SCIENCE. 



into Minnesota, as far as Traverse Lake, it had a length of more than 600 miles 

 and a breadth of 250 miles. 



Its greatest tributary was the Saskatchewan — a river nearly as large as the 

 Missouri. It flowed in a deep broad canon now partly filled with drift deposits^ 

 in some places, to two hundred feet or more in depth. 



Another tributary, but of a little less size, was the Assiniboine, now empty- 

 ing into the Red River, at the City of Winnipeg. Following up this river, 

 in a westerly direction one passes into the Qu' Appelle Valley, — the upper 

 portion of which is now filled with drift, as first shown by Prof. H. Y. Hind. 

 This portion of the valley is interesting, for through it, before being filled with 

 drift, the south branch of the Saskatchewan River formerly flowed, and consti- 

 tuted an enormous river. But subsequent to the Great River Age, when choked 

 with drift, it sent its waters to the north Saskatchewan as now seen. There were 

 many other changes in the course of the ancient rivers to the north, but I can- 

 not here record them. 



As we have seen, the ancient Mississippi and its tributaries were vastly larger 

 rivers than their modern representatives. At the close of the Great River Age, 

 the whole continent subsided to many hundred feet below its present level, or 

 some portions, to even thousands of feet. During this subsidence, the Mississippi 

 States north of the Ozark Mountains formed the bed of an immense lake, into 

 the quiet waters of which were deposited soils washed down by the various 

 rivers from the northwestern and north central States and the northern territories 

 of Canada. These sediments, brought here from the north, constitute the bluff 

 formation of the State, and are the source of the extraordinary fertility of our lands,. 

 on which the future greatness of our State depends. However, time will not per- 

 mit me to enter into the application of the facts, brought forward, to agricultural 

 interests. But although this address is intended to be in the realm of pure science, 

 I cannot refrain from saying a word to our engineering students as to the applica- 

 tion of knowledge of river geology to their future work. The subject of river 

 geology is yet in its infancy, and I have known of much money being squandered 

 for want of its knowledge. In one case, I saved a company several thousand 

 dollars, though I should have been willing to have given a good subscription to 

 have seen the work carried out from the scientific point of view. 



I will briefly indicate a few interesting points to the engineer. Sometimes 

 in making railway cuttings it is possible to find an adjacent buried valley through 

 which excavations can be made without cutting hard rock. In bridge building 

 especially, in the western country, a knowledge of the buried valleys is of the 

 utmost importance. Again, in sinking for coal do not begin your work from the 

 bed of a valley, unless it be of hard rock, else you may have to go through an 

 indefinite amount of drift and gravel ; and once more, in boring for artesian wells, 

 it sometimes happens that good water can be obtained in the loose drift filling 

 these ancient valleys; but when you wish to sink into harder rock, do not select 

 your site of operations on an old buried valley, for the cost of sinking through 

 gravel is greater than through ordinary rock. 



