PHYSICAL FEATURES. 



59 



surface outlet. The depth of few lakes is known, but that of those in the moraines and outwash 

 aprons appears to be as great as that of lakes of corresponding size in the moraines and outwash 

 aprons of northern Indiana — 40 to 100 feet or more. As in Indiana, many of the lakes contain 

 large deposits of marl 40 feet or less in depth. A few lakes along the shore of Lake Michigan are 

 shut in by dunes and are shallow; a few in Monroe County are in sink holes in the limestone; 

 and a few in Alpena and Presque Isle counties are in sink holes or in rock basins. Long and 

 Grand Lakes in the counties last mentioned are situated at the base of rock escarpments but 

 owe their existence, at least in part, to drift obstruction. 



The following table contains a list of SI lakes (all that have an area of a square mile or more), 

 with their approximate altitudes and their areas as estimated from the county maps in the Tacka- 

 bury atlas. They aggregate 390 square miles and probably embrace half the inland-lake area 

 in the peninsula. Most of the altitudes have been determined by aneroid barometer or estimated 

 from altitudes of neighboring railway stations. A few stand near the level of Lake Michigan 

 and a few, as indicated in the table, have been determined by spirit level. 



Lakes in the southern peninsula of Michigan having an area of 1 square mile or more. 



Houghton 



Pine 



Mullet 



Torchlight 



Burt 



Black 



lupins 



Hubbard 



Crystal 



Elk 



Glen 



Carp 



Grand 



Long 



Muskegon 



Walloon or Bear. 



Douglass 



Crooked 



Intermediate 



Portage 



Long 



Bis Sable 



Bin Clam 



Platte 



Missaukee 



St. Helens 



Tawas 



Portage...* 



White 



Grass 



Carp 



Gun 



Gull 



Van Etten . . 



Duck 



Green 



Round 



Black 



Little Clam . 



Roscommon . 

 Charlevoix... 

 Cheboygan... 



Antrim 



Cheboygan... 



.do. 



Roscommon. 



Alcona 



Benzie 



Antrim 



Leelanau 



.do. 



Presque Isle 



Alpena 



Muskegon 



Charlevoix-Emmet- 

 Cheboygan 



Emmet 



Antrim 



Manistee 



Grand Traverse 



Wexford 



Benzie 



Missaukee 



Roscommon 



Iosco 



Crawford 



Otsego 



Manistee 



Muskegon 



Antrim 



Emmet 



Barry 



Kalamazoo 



Iosco 



Ornm.l Traverse. 



.do. 



Antrim... 

 Ottawa... 

 Wexford.. 



Sq.miJcs. 



Altitude 



above sea 

 level. 



1,280 

 a 595 

 a 1,240 

 1,150 

 585 

 1,130 

 1,270 

 a 760 



Rush 



Coldwater.. 



Marble 



Cedar 



MallisKv . . . 

 East Twin. 

 West Twin 



Grass 



Big Star.... 

 Chippewa . . 



Cass 



Austin 



Crooked — 

 Diamond.. 



Klinger 



Turtle 



Odessa 



Orchard... 



Corey 



Paw Paw . . 



Sage 



Silver 



Au Sable.. 

 Fremont. . 



Pierce 



Devil 



Reed 



Devil 



Long 



Crystal 



Lakeville . . 



Long 



Crooked.. . 

 Thumb . . . 



Bass 



White 



Whitmore. 

 Portage . . . 



Pine 



Wamplers . 



Alcona 



Kalkaska 



Montmorency . 



.do. 



Benzie 



Lake 



Mecosta 



Oakland 



Kalamazoo . 

 Barry 



St. Joseph 



Montmorency... 



Ionia 



i lakland 



St. Joseph 



Berrien 



Ogemaw 



(-rand Traverse. 



Oceana 



Newaygo 



Emmet 



Alpena 



Kent 



Lenawee 



(renesee 



Montcalm 



< lakland 



Kalamazoo 



Missaukee 



Charlevoix 



Mason 



< lakland, 



Washtenaw 



.do. 



Sq. miles. 



1.25 

 1.25 

 1.25 

 1.25 

 1.25 

 1.25 



i Determined by aneroid barometer. 



b Alexander Wi'nchell gives this altitude as 1,170 feet. 



c Spirit levels run by Prof. J. B. Davis, of the University of Michigan. 



<* Determined by Prof. A. W. Grabau, of Columbia University. 



e Spirit levels run by J. J. Hubbell, chief engineer of the Manistee & Northeastern Railroad. 



STREAMS. 

 PREGLACIAL DRAINAGE. 



Concerning the course of preglacial drainage very little can be determined in a region 

 with such great drift accumulations. 



In Indiana borings from the vicinity of Lafayette westward have disclosed a preglacial 

 valley, with a rock floor scarcely 300 feet above sea level, running westward a little north of 

 Wabash River. The borings indicate that a deep valley leads into this from the north and 



