369. View of Mackinac Island from the direction of St. Ignace 342 370. The “Sugar Loaf”, a stack of Lake Algonquin upon Mackinac Island 342 371. Beach ridges in series on Mackinac Island 343 372. Notched stack of the Nipissing Great Lakes at St. Ignace 343 373. Series of diagrams to illustrate the evolution of ideas concerning the uplift of the lake region since the Ice Age 344 374. Map of the Great Lakes region to show the isobases and hinge lines of uptilt 345 375. Series of diagrams to indicate the nature of the recovery of the crust by uplift when unloaded of an ice mantle 346 376. Portion of the Inner Sandusky Bay, for comparison of the shore line of 1820 with that of to-day 350 377. Ideal cross section of the Niagara Gorge to show the marginal terrace 353 378. View of the bed of the Niagara River above the cataract where water has been drained off 353 379. View of the Falls of St. Anthony in 1851 354 380. Ideal section to show the nature of the drilling process beneath the cataract 355 381. Plan and section of the gorge, showing how the depth is proportional to the width 355 382. Comparative views of the Canadian Falls in 1827 and 1895 356 383. Map to show the recession of the Canadian Fall 357 384. Comparison of the present with the future falls 358 385. Bird’s-eye view of the captured Canadian Fall at Wintergreen Flats 358 386. Map of the Whirlpool Basin 360 387. Map of the cuestas which have played so important a part in fixing the boundaries of the lake basins 361 388. Bird’s-eye view of the cuestas south of Lakes Ontario and Erie 362 389. Sketch map of the greater portion of the Niagara Gorge to illustrate Niagara history 363 390. Snowdrift hollowing its bed by nivation 368 391. Amphitheater formed upon a drift site in northern Lapland 369 392. The marginal crevasse on the highest margin of a glacier 370 393. Niches and cirques in the Bighorn Mountains of Wyoming 371 394. Subordinate cirques in the amphitheater on the west face of the Wannehorn 371 395. “Biscuit cutting” effect of glacial sculpture in the Uinta Mountains of Wyoming 372