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who went on bicycles nothing; and all were at home 

 before six o'clock. 



The lesson on stream erosion was followed by two 

 on the work of waves along the shores of Lake Erie. 



We went first to Glenn wood Beach, east of the 

 citv. Here there is a continuous beach one hundred 

 feet wide and several miles long, including Glennwood, 

 Villa, and Euclid Beaches, back of which rises a bluff of 

 clay and sand to a height of forty feet. 



First we noted the direction of the wind which was 

 from the west, the prevailing direction along the lake; 

 and also the angle at which the waves met the shore, 

 about forty-five degrees. 



Approaching close to the water's edge, we observed 

 the zigzag course of the pebbles which were being 

 moved along by the waves; and bits of wood were 

 thrown in and traced for several rods down the beach. 

 This gave us the general direction in which the lake 

 moves the waste along the shore. 



As far as ve could see out under the shallow water 

 were great beds of ripple marks in the sand. These we 

 studied carefully by cutting them through with a stick 

 and watching the waves fill the gaps again. The 

 pupils had already noticed the ripple marks in the 

 many stone sidewalks of the city ; now the origin of 

 those marks was understood. Back a few feet from 

 the water was the well marked crest-line of the beach, 

 sloping sharply toward the lake and more gently 

 toward the base of the cliff. All the time we were 

 walking along this ridge, studying its mode of form- 

 ation and its direction parallel to the shore. Finally 

 we walked close to the edge of the bluff. Here drift- 

 wood had been heaped by storms ; and beneath the 

 overhanging wall were many sea-caves. A storm of 

 that very week had brought down great masses of clay 

 large enough to fill a wagon; and some of the boys 

 climbed to the top ot the bluff and dislodged more. 

 Then we could see how the shores of the lake are re- 

 treating, and how the owners of land there must 



