NATURE STUDY. 



PUBLISHED UNDER THE AUSPICES OF THE 



Manchester Institute of Arts and Sciences. 



Vol. IV. January, 1904. No. 8. 



Two Places of Interest. 



BY JOSEPH N. PROKES. 



If we glance at the map of North America we find that 

 the state of Minnesota is situated exactl}- in the central 

 part of the continent. We learn from students of geology 

 that about ten thousand years ago much of the surface of 

 North America was covered by a thick sheet of ice, which 

 advanced slowly from the north and more recently as slow- 

 I3' retreated. The period of ice- advance is known to geol- 

 ogists as the glacial period. Throughout Minnesota are 

 to be found traces of this glacial action. 



Four miles west from the village 'of Jackson, Jackson 

 county, Minnesota, lies a sheet of water known as Clear 

 L,ake, and this is a typical hollowed out glacial lake. The 

 banks are high, formed out of drift boulders of every di- 

 mension, round and smooth, piled irregular!}-, and here is 

 the Mecca of the collector. Along this hard gravel shore 

 beautiful specimens of quartz, agate, jasper and carnelian 

 are found, varying in size from a filbert to some weighing 

 four ounces. 



