784 WARREN UPHAM 



than my mapping in the United States Geological Survey mono- 

 graph. The incoming of settlers, with the construction of roads 

 and railways and clearing away the forest in many places to 

 open farms, now gives opportunity to trace the courses of the 

 beaches through the country adjoining the Rainy River, where Mr. 

 Leverett maps a finely developed shoreline, referred to the Campbell 

 stage of Lake Agassiz, for the distance of about 40 miles, from near 

 Roosevelt east-southeastward to Baldus, having the height along 

 all this isobasic course of about 1,120 ft. above the sea. This alti- 

 tude is as great as the highest of the Campbell beaches has on the 

 eastern slope of Riding Mountain in Manitoba, which shows that 

 the isobase of the land uphft there crossing the lake area runs about 

 N^- 55° W. In other words, the direction of maximum uplift is ap- 

 proximately N. 35° E. 



With the light thus received, we may quite confidently corre- 

 late the series of eleven beach ridges noted by the profile on Beltrami 

 Island and northward, from 1,215 to 1,087 ft., as representing the 

 second Norcross, Tintah, and Campbell stages of Lake Agassiz, 

 but with other subdivisions than were noted in my tabulation for 

 the latitudes of Gladstone and Valley River, Manitoba. 



The present report and its large detailed map of the surface 

 formations of the northwest quarter of Minnesota, on the scale of 

 8 miles to an inch, are designed primarily to instruct and aid 

 farmers, drainage engineers, road-builders, and others, for the 

 development and utilization of the agricultural resources of this 

 state. 



GlaciaHsts and other geologists will desire that Mr. Leverett 

 present later, for the entire state of Minnesota, a more specific 

 description and discussion, and additional maps, setting forth the 

 successive borders of the waning ice-sheet, as shown by their 

 moraines, with the corresponding stages of growth of Lake Agassiz, 

 and treating fully of the erosion, transportation, and deposition 

 of the various drift formations. Such maps will be much improved 

 by insertion of contour lines, and by notations of altitudes of lakes, 

 rivers, railway stations, etc., whereby the form of the land surface 

 and the elevation above the sea will be shown, giving information 

 that seems indispensable for a definite understanding of the drift, 

 loess, and glacial lakes. 



