Baii-ed Beaches of La he Michigan. 187 



soutli as at the time of tlie Upper beach, for no beacli lines were observed 

 west of the Illinois Central railroad. East from this railway, however, a 

 well-defined beach exists. It assumes sufficient prominence to be notice- 

 able in Sees. 27 and 28, Tp. 36, R. XIV E., there being on these sections 

 a low beach 10 — 15 feet high, a portion of which is a rocky escarpment, 

 but the remainder is till across Thorn Creek, from the east end of this 

 bench in Sec. 35 of the same township, a beach line of much strength is 

 developed. It is 40 — 80 rods wide, and has dunes 20 feet or more in heighth. 

 It lias a nearly due east course for three miles in Illinois, passing through 

 the village of Lansing. It continues into Indiana with the same course, 

 lying along the north border of Cady marsli, to the eastern end of the 

 marsh, thence it continues with a cousre slightly north of east to Liver- 

 pool, where it becomes associated with the Upper beach lines, and its 

 further distribution is given in connection with those beaches. The 

 Indiana portion of this beach west of its junction with the Upper beaches, 

 is a single ridge of sand slightly pebbly in places. It drifts into dunes at 

 several jsoints, but none were observed whose height exceeds 40 feet 

 above the jDlain at the base of the ridge. The ridge where not drifted into 

 dunes, is some 15 feet above its immediate base, and has a width of 40 

 rods more or less. Its elevation at Lansing, Illinois, is 43 ?eet above Lake 

 Michigan. No other elevations are at hand at time of writing. 



Between this beach line and the Calumet river there is a plain underlain 

 by pebbly clay, and having scarcely any coating of sand or gravel. The beach 

 deposits seldom extend more than 80 rods north from the base of the ridge. 



THE LOWER BEACH. 



The most northerly point at which this beach has been identified is at 

 Evanston, Illinois. It rises here nearly 25 feet above the lake, and 

 has at its northern extremity a width of 30 rods or more. It passes 

 through the eastern part of the city of Evanston, and its course from Evans- 

 ton to Eavenswood is nearly south. From Ravenswood it bears slightly 

 east of south, to Lincoln Park in the north part of Chicago, and passes 

 through the western part of this park. In the early days of Chicago, the 

 ridge was developed at intervals through the eastern part of the city, but 

 all traces are now removed. In the southeast part of Chicago, and in 

 Hyde Park, the beach has not been removed. Between Hyde Park and En- 

 glewood it is well developed, having an extreme elevation of 19 feet 

 above the lake. From Englewood it passes south through Sec. 21, to 

 the center of Sec. 28, Tp. 38 N., R. XIV E. South from here it is a low 

 belt of land i — f mile in width, and rising scarcely 10 feet above Lake Michi- 

 gan, which connects the low lands west of Chicago, and in the Stock Yards 

 in the southwest part of Chicngo. with the low land along Lake Michigan, 

 near Lake Calumet. 



South from this low belt there are two beaches, neither of which are 

 the exact e(iuivalents in height of the ridge we have just traced. The in- 

 nermost of these beaches extends from the head of Lake Calumet, east of 

 Pulman, northwest to the vicinity of South Lynn. In is a bench 4 — 6 feet 



