QUATERNARY FORMATIONS THE DRIFT. 233 



diate steps to save our territory from the voracity of Lake Michigan. 

 The question naturally arises, Is this advance of the lake due to a 

 subsidence of the land ? This question very materially affects the value 

 of all the property along the shore, for if this advance is due to a sub- 

 sidence, it is largely beyond our control, and where and when it will 

 end could only be conjectured, and it would be practically useless to 

 attempt to permanently stay its progress. But fortunately there no- 

 where appears to be any evidence of such subsidence. If any consid- 

 erable movement were in progress it would doubtless have been no- 

 ticed in some of the harbors, but none has been detected. 



It has been shown above that the entire Wisconsin shore of the lake 

 has in recent geological times stood from 10 to 50 feet lower than at 

 present, reckoning the water level as constant, or that the lake 

 is now at a lower level than at that period. It is also known from 

 the same facts that in a period of years that must be reckoned by 

 hundreds, if not thousands, the lake has on the whole made no ad- 

 vance. Along 120 out of 200 miles of lake shore the present line is 

 farther east than the ancient one, and the territory of Wisconsin 

 seems to be somewhat greater now than then. The encroachment is 

 hence not a cause of grave apprehension, although it demands ener- 

 getic attention. 



The material washed out from the shore is borne southward and 

 accumulates rapidly on the north side of all the solid piers, that ex- 

 tend out from the shore, forming triangular areas of " made land," as 

 it is termed with questionable propriety. 



DUNES. 



A few miles south of Sheboygan, and at several other points along 

 the shore, the narrow area between the ancient beach line just men- 

 tioned and the present one, is covered with beach sand which the 

 winds are still engaged in heaping up into dunes, which are being cut 

 and shifted after the manner of that formation. From their nature 

 and surroundings they have not and probably never will become large 

 or conspicuous, and are mentioned here rather as a matter of interest 

 than of importance: 



EROSION AND DEPOSIT IN PROGRESS. 



Aside from the special case of lake encroachment already mentioned, 

 there is a general work of erosion and deposit in progress, as is patent 

 to the commonest observation. This work in the soft drift deposits 

 progresses easily arid rapidly. The hills are being swept down and 



