292 F. Leverett — Correlation of Moraines 



The principal embayments in the ancient shore are at Black, 

 Huron and Sandusky rivers. At Vermillion river there was 

 scarcely an} T embayment. These embayments do not owe their 

 existence to different rates of erosion of the shore under wave 

 action, but were probably produced by the ice-sheet previous 

 to the occupancy by the lake, the effect of the ice-sheet being 

 "to broaden the mouths of old valleys which it entered. The 

 lake nowhere cut back its shore a mile, and usually but a few 

 rods while it occupied this beach, as may be determined by a 

 restoration of the original slope on which it was carved. 



It is not improbable that the terrace noted by Dr. Spencer 

 at Ypsilanti, Michigan, should be correlated with the second 

 b»each instead of with the Van Wert ridge, for the next lower 

 beach observed by him near that city is below the level of the 

 Leipsic beach, the altitude being but 161 feet above Lake Erie 

 or about the altitude of the third or Belmore beach of north- 

 western Ohio. If the Ypsilanti terrace proves to be the cor- 

 relative of the second beach there is a differential uplift of 20 

 feet between Bryan and Ypsilanti, a distance of about 50 miles. 



Certain altitudes in the above table will no doubt raise the 

 question as to the possibility of correlating this beach with the 

 Van Wert ridge. From Van Buren to Bellevue it has appar- 

 ently as great an average altitude as the Van Wert ridge. 

 Since the stations included between these towns have altitudes 

 obtained from several independent surveys and show essential 

 harmony it is unlikely that they contain great errors or exag- 

 gerations of the altitude of the beach. A beach formed subse- 

 quent to the retreat of the ice, as the Leipsic beach was, cannot 

 be correlated with one f ormed while the ice-sheet still occupied 

 the Blanchard moraine. Reasons have already been given for 

 considering the Van Wert ridge the correlative of the Blan- 

 chard moraine, and to my mind they hold good even though por- 

 tions of the Leipsic beach be as high as the Van Wert ridge. 

 The Leipsic beach certainly fluctuates in altitude. I have fol- 

 lowed it continuously from Van Buren to McComb and made 

 certain that it represents but a single stage of the lake ; yet 

 there is a difference of 14 feet in the altitude of these stations 

 (seven miles apart). The altitudes being obtained by inde- 

 pendent surveys it is possible that a portion of the difference 

 may be due to their not checking in their results, but probably 

 only a small portion. A study of the profiles of the L. S. & 

 M. S. E. R. reveals the fact that the beach is at least 10 feet 

 higher at Bellevue than it is between Cleveland and Elyria, 

 and its survey is carefully checked since it comes down nearly 

 to lake level both at Sandusky and Cleveland. It is, therefore, 

 well established that in the vicinity of Bellevue the beach has 

 suffered a slight differential elevation. This elevation may 



