344 W. UPHAM PREGLACIAL AND POSTGLACIAL VALLEYS. 



extent a terrace cut by waves in the till, with a somewhat steep descent 

 of 10 or 15 feet. At St. John's Hospital the princij)al beach ridge, raised 

 3 to 5 feet above the general surface of the till, lies about 20 rods south 

 of Detroit street, and has a width of 6 to 10 rods. Its gravel, stones and 

 cobbles var}^ in size up to 6 or 8 inches in diameter. From the junction 

 of Lake avenue and Detroit street eastward this shore lies on the Cuya- 

 hoga or Cleveland delta sand plain to the limits of the city and beyond. 

 It passes close south of the public square, by the intersection of Prospect 

 and Erie streets, and thence coincides nearly with the course of Euclid 

 avenue, the crest of its broad, massive swell being at first south, but soon 

 and for a long distance close north of this most beautiful avenue. In 

 the vicinity of Wade park the beach swell, like a huge low wave, runs a 

 fourth of a mile, more or less, northwest of Euclid avenue and nearly 

 parallel with it. Th.e crest of tlie beach varies from 95 to 100 feet above 

 the lake, having been formed when the glacial lake Warren held a slightly 

 varying plane (in low and high stages and in calm and storms) at 90 to 95 

 feet, or 665 feet, very nearly, above the present sea level. 



The Euclid Avenue beach marks the princii)al and lower one of the 

 two or more parallel and companion shores which J.everett groups to- 

 gether as the Crittenden beach, so named by Gilbert from Crittenden in 

 southwestern New York, near which this shore has its eastern land ter- 

 mination, the country farther east and north having been enveloped by 

 the wanin<; ice-sheet. In Cleveland the third or Woodland Avenue beach, 

 before described, is the upper niem])er of the coni})ound Crittenden levels . 

 but there ai)pears to be sufficient reason for considering these two shores 

 separately, as they are divided by a vertical interval of 20 to 30 feet along 

 the Avhole extent of the south side of lake P2rie. 



CORRELATION WITH UTAGES OF THE GLACIAL RECESSION. 



The foregoing description of the Leipsic beach shows that the time of 

 its formation extended through that of the Newburg moraine and prob- 

 ably u}) to the time of the Euclid moraine. In two very valuable con- 

 tributions to the glacial geology of this region,'!" Mr Leverett has proved 

 the successive glacial lake stages to have been contemporaneous with 

 stages of the glacial retreat defined by four distinct moraines. The 

 Leipsic beach he sui)posed to have been wholly formed before and during 

 the accumulation of the Newburg moraine, which he thought to be repre- 

 sented by the moderately rolling and hilly surface of till a half mile to 

 one mile south of Brooklyn. This area may so represent the moraine, or 

 at least a southern branch of it, but doubtless much or nearly all of its 



*Am. Journal of Science, III, vol. xliii, pp. 281-301, with maps, April, 1892; vol. 1, pp. 1-20, with 

 map, July, 1895. 



