CHAPTEK VI. 



BEACHES AND DELTAS OF THE HERMAN STAGES. 



In this and the two following chapters the shore-lines of Lake Agassiz 

 are described in considerable detail, with notes of then- altitude and of the 

 topogi'aphic features of their tracts marked by erosion, and of the more 

 extensive tracts where beach ridges were accumulated. The fullness and 

 convincing character of the evidence that these are the shore-lines of an 

 ancient lake of vast size, occupying the Red River Valley and the present 

 lake region of Manitoba, are thus impressively exhibited; and the diverse 

 phases of the results produced by waves and shore currents are brought 

 into comparison. 



Ten plates (XXIH to XXXII), on the scale of 6 miles to an inch, 

 covering consecutive areas as indicated on PI. XXII, display the definite 

 geographic location of the shores; and all their more remarkable portions 

 are described, with statement of the sections or often the quarter-sections 

 under consideration, in the text. The arrangement of the sections in each 

 township is shown in fig. 1, on page 11. 



Many of the farmers whose houses are built on or near to the old 

 beaches have decided to their own satisfaction, as I learned by conversation 

 with them during the progress of these surveys and levelings, that these 

 beach ridges of gravel and sand are the same as those of how existing lakes 

 of large size, and that consequently the flat Red River Valley so bounded 

 was once the bed of a great lake. These residents will be enabled by the 

 following descriptions and maps to trace the continuity of the shores seen 

 near their own homes to distances of many miles away and, indeed, around 

 all the prairie portion of the ancient lake. 



With the progress of agricultm-e, which is rapidly bringing all this lake 

 bed into cultivation, certain features of the deserted shores that were very 

 distinct at the time of my examination will doubtless be obscured or oblit- 

 erated. Many of the groves here noticed as occurring along stream courses 



