If our conclusions have been correct, the several lake basins should now be behaving in different ways as regards the changes upon their shores. If it is true that the lines of greatest uptilt run north-northeasterly, there should be, speaking broadly, a “spilling over” of waters upon the south-southwesterly shores and a laying bare of the north-northeasterly shore terraces of the basins. This should, however, be true only of basins whose outlets are to the northeastward of the existing main hinge line of uptilt. Lake Huron, having its outlet at the southern margin of its basin, should not have its waters encroaching upon the southern shore, for the simple reason that any continued uptilt of the basin can only have the effect of pouring more water through the outlet. Lake Michigan and Saginaw Bay, which are arms of the Huron basin, ought, however, to become flooded upon their southern shores, _were it not that the hinge line of uptilt to-day lies to the northward of the outlet at Port Huron, and, further, that the two connecting channels still have their beds lower than the sill of the outlet channel_. Now the evidence goes to show that no encroachment of waters is occurring upon the Chicago shore of Lake Michigan, and although the shores of Saginaw Bay are so excessively flat as to reveal slight changes of level by large migrations of the strand, yet the ancient meander posts fixed by the early surveys are still found near the water’s edge. =Drowning of southwestern shores of Lakes Superior and Erie.=—Within the basins occupied by Lakes Superior and Erie, a wholly different condition is found. In each case the outlet is found to the northeastward (Fig. 374, p. 345), and the northwesterly trend of the isobases from these outlets is responsible for a continued elevation from uptilt of the outlets with reference to the western and southern shores. In consequence, the waters are encroaching upon these shores, and rivers which there enter the lake are drowned at their mouths, with the formation of estuaries. Upon Lake Superior these changes are very marked near Duluth and particularly in the St. Louis River, within which, since the early treaty with the Indians, certain rapids have disappeared and submerged trunks of trees are now found in the channel of the river. As far east as Ontonagon essentially the same conditions are found. Upon the shores within the Porcupine Mountain district, the waters are clearly rising. Here old cedar trees may be seen, in some cases dead but still upright and standing in from six to eight inches of water a number of feet out from the present shore, while others near the shore, but upon the land and still living, are washed by the waves, and losing their lower bark in consequence. An old road along the shore has had to be abandoned because of the encroaching water.