cop.<^ 
 
 NE-SAW-IE-WON 
 
 A TALE OF 
 
 .R'f^ATERS THAT RUN DOWN 
 
 FROM LAKE SUPERIOR TO THE SEA 
 
 HELEN M. MARTIN
 
 it
 
 GREAT LAKES 
 REGION
 
 LIBRARY OF THE 
 
 UNIVERSITY OF ILLINOIS 
 
 AT URBANA-CHAMPAIGN 
 
 IN MEMORY OF 
 
 STEWART S. HOWE 
 
 JOURNALISM CLASS OF 1928 
 
 STEWART S. HOWE FOUNDATION 
 
 551.31 
 M364n 
 cop. ?.■ 
 
 I .H.S.
 
 NE-SAW-JE-WON
 
 SPECIAL EDITION 
 
 For Private Distribution 
 
 Copyright, 1939, by 
 M. D. Harbaugh 
 
 Printed in the United States of America by 
 
 The William Feather Company 
 
 Cleveland, Ohio
 
 as the Ottawas say 
 
 A Tale of 
 THE WATERS THAT RUN DOWN 
 FROM LAKE SUPERIOR TO THE SEA 
 
 by 
 HELEN M. MARTIN
 
 To Dr. Frank Leverett and to the NLemory of 
 Mr. Frank B. Taylor: 
 
 Through nearly half a century Dr. Leverett and Mr. Taylor 
 explored and deciphered the records made by the continental 
 glaciers during the Ice Age. Front their studies was revealed 
 the fascinating history of the Great Lakes. They travelled, 
 mainly on foot, thousands of miles along the glacial moraines 
 and over the beaches, shores and beds of the ancient lakes, 
 measuring, recording and mapping as they went. They em- 
 bodied their observations and conclusions in many scientific 
 publications. Their ivork and their lives have been an inspira- 
 tion to other geologists who have folloived their footsteps and 
 to many students ivho absorbed, in their lecture halls, the 
 interesting story of glaciation. Much of this tale — NE-SAW- 
 JE-WON, of ^^the waters that run down from Lake Superior 
 to the sea'' — is draivn from their classic volume, ''The 
 Pleistocene of Michigan and Indiana and the History of the 
 Great Lakes'' and from Dr. Leverett' s ''Moraines and Shore 
 Lines of the Lake Superior Region" — publications of the 
 United States Geological Survey.
 
 ^ //n. rOREWORD 
 
 ^ <P 
 
 THE Story of the Great Lakes, familiar to geologists the world 
 over, is so romantic that it should be known to all who find 
 pleasure in understanding natural environment and the man- 
 ner of its development. The story should have a strong appeal to 
 all who know and love the broad waters of the Great Lakes and the 
 picturesque beauty of their shores. 
 
 Several years ago a group of business men, accustomed to a mid- 
 summer trip together on a lake freighter, each day afloat gathered to 
 discuss subjects of mutual interest. One of them, a geologist, con- 
 tributed a series of informal talks on the Geology of the Great 
 Lakes Region and the History of the Lakes, drawing illustrations 
 from the rocks and shore features that could be observed from the 
 ship. So much interest was aroused by these discussions that eventu- 
 ally it was planned to have the story written in brief, popular form, 
 with the necessary maps and illustrations, so that it could be read at 
 leisure and retained as a memento of such voyages. 
 
 Years passed without any action being taken on this idea, until 
 in the fall of 193 8, Miss Helen M. Martin, geologist, associated with 
 the Michigan Geological Survey, was engaged to prepare the manu- 
 script. As she is intimately familiar with the geology of the lakes 
 region and is a former student of Dr. Frank Leverett (who, with 
 the late Frank B. Taylor, is mainly responsible for what is known 
 of the origin and development of the Great Lakes), Miss Martin is 
 especially qualified for this undertaking. In the spring of 1939, 
 her manuscript, sketch maps and photographs were turned over to 
 Mr. M. D. Harbaugh, who has done the editorial work, prepared 
 final drawings, and designed and directed the publication. 
 
 For this little volume, the reader is indebted to Pickands, Mather 
 and Company, The M. A. Hanna Company, The Cleveland-Cliffs 
 Iron Company, and Oglcbay, Norton & Company. They join with 
 others who have had a part in giving form to the idea that initiated 
 this booklet, in hoping that NE-SAW-JE-WON will be found 
 interesting and instructive. 
 
 M. D. llavbangh 
 Hanna Building 
 Cleveland, Ohio 
 July, 19)9
 
 NE-SAW-JE-WON 
 CONTENTS 
 
 Page 
 
 Sketch of the Story 9 
 
 Setting for the Ice-Age Drama — The Rock Formations and 
 
 Pre-Glacial History of the Great Lakes Region 11 
 
 The Glacial Period and its Records 20 
 
 The Records Made by Rivers and Lakes 28 
 
 Lake Maumee — the First of the Glacial Lakes 33 
 
 Early Lake Chicago; Lake Jean Nicolet 34 
 
 The Second Stage of Lake Maumee 37 
 
 The Third Stage of Lake Maumee 38 
 
 Lake Saginaw 39 
 
 Lake Chicago 41 
 
 Lake Arkona 41 
 
 Expanding Lake Chicago 43 
 
 Restored Lake Saginaw; Lake Newberry 43 
 
 Lake Whittlesey 44 
 
 Lake Wayne 45 
 
 Early Lakes of the Superior Basin 46 
 
 Lake Warren 47 
 
 Lake Duluth 47 
 
 Lake Elkton 49 
 
 Early Lake Algonquin; Lake Tonawanda 53 
 
 Niagara River and the Birth of the Falls; Beginning of 
 
 Independent Lake Erie 5 5 
 
 The Second Stage of Lake Algonquin; Lake Iroquois; 
 
 Lake Erie 57 
 
 Crustal Movements of the Earth 59 
 
 More Work of Niagara River 62 
 
 The Records of Algonquin Time 63 
 
 The Nipissing Great Lakes 69 
 
 The Modern Great Lakes 78 
 
 The Story Unfinished 81
 
 CONTENTS 
 
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 Maps 
 
 Page 
 Regional Map of the Great Lakes 
 
 1. — Geological Map of the Great Lakes Region 12 
 
 2. — Glacial Map of North America 20 
 
 3. — Glacial Map of the Great Lakes Region 22 
 
 4. — First of the Glacial Lakes — Maumee and Chicago 32 
 5. — Glacial Lakes Maumee, Saginaw, Chicago, and 
 
 Jean Nicolet 36 
 
 6. — Diagram Showing Water Levels of the Various 
 
 Stages of Lakes in the Erie Basin 38 
 
 7. — Glacial Lakes Arkona and Chicago 40 
 
 8. — Glacial Lakes Whittlesey, Saginaw, Chicago, 
 
 AND Newberry 42 
 
 9. — Glacial Lakes Warren, Chicago, and Duluth 48 
 
 10. — Glacial Lakes Elkton (formerly Lundy), 
 
 SiMcoE, Chicago, and Duluth 50 
 
 11. — Glacial Lakes Duluth, Chicago and early 
 
 Algonquin; Independent Lake Erie 52 
 
 12. — Diagram of Niagara River Gorge 54 
 
 13. — Glacial Lakes Algonquin and Iroquois; Lake Erie 56 
 
 14. — Glacial Lakes Algonquin and Iroquois; Lake Erie 60 
 15. — Final Stage of Glacial Lake Algonquin; Lake 
 
 Erie and Lake Iroquois 68 
 
 16. — Nipissing Great Lakes, Lake Erie and Lake Ontario 70 
 
 Photographs 
 
 1. — "Pictured Rocks" Rampart of Cambrian Sandstone 15 
 
 2. — Falls of Tahquamenon River 16 
 
 3. — Beach on Mackinac Island 30 
 
 4. — Arch Rock, Mackinac Island 64 
 
 5. — Sugar Loaf Rock, Mackinac Island 65 
 
 6. — Pointe Aux Barques, Sea Caves and Arches 66 
 
 7. — Castle Rock, St. Ignace, Michigan 71 
 
 8. — The "Fortress" of the Pictured Rocks 72 
 
 9. — Cliff and Sea Cave 72 
 
 10. — Stacks and Sea Caves 73 
 
 11. — Chapel Rock 74 
 
 12.— Wave-Cut Cliffs 74 
 
 13. — Miner's Castle 75 
 
 14. — Grand Marais Dunes 76 
 
 15. — Nla-Gara Falls 80
 
 NE-SAW-JE-WON 
 
 Sketch of the Story 
 
 A BOUT a million years ago, when in far-off Java Pithe- 
 /-\ canthropus Erectus, the Ape-man, was fumbling his 
 -^ -*- way to the man species, a river system occupied the 
 Great Lakes region, flowing from the highlands of eastern 
 Canada probably to the Gulf of Mexico. But about that time 
 glaciers, which developed far north in the Hudson Bay region, 
 started to move southward and eventually erased or buried 
 much of the record of that river. Half a million years later 
 the Peiping man, Sinanthropus, was buried in the limestone 
 caves of China, and in North America the continental ice 
 sheet reached as far south as Kansas. Then during a time of 
 genial climates the ice front retreated, and perhaps the ice 
 melted almost entirely from the region which is now the 
 United States. Vegetation followed the northward movement 
 of the ice front, and a rich soil was developed over the glaciat- 
 ed region of North America. In Europe the Heidelburg and 
 Piltdown men made their appearance, but we have no evi- 
 dence as yet that man had arrived on this continent. Then 
 some 150,000 to 200,000 years ago, when the Neanderthal 
 man was living before the ice front in Europe, the ice re- 
 advanced in North America. It covered the Great Lakes 
 region and moved as far south as southern Illinois near Cairo, 
 to a point ten miles south of the Ohio River near Cincinnati, 
 and to Beaver Falls in western Pennsylvania. North America 
 became the most icebound of continents. In the centers of 
 accumulation about the Hudson Bay region the ice is esti- 
 mated to have been from three to six miles in thickness. 
 
 Thirty-five thousand years ago, when the Cro-Magnon 
 — the first of modern men — were hunting the mastodon in 
 southern Europe and drawing rude pictures of their kill on
 
 NE-SAW-JE-WON 
 
 the walls of their cave homes in southern France, the North 
 American ice sheet again had melted back some hundreds of 
 miles ; in northwestern Ohio pools of water gathered along its 
 front, and the Great Lakes had their beginning. 
 
 When the Folsum-Yuma men were hunting bison on our 
 western plains, twenty thousand years ago, the glacier melted 
 away from the ledge of limestone at Lewiston, New York, 
 on the Niagara River, and Niagara Falls was born. Ten thou- 
 sand years later, when our present civilization was dawning in 
 the Near East, the ice had melted entirely from the Great 
 Lakes basins; only a small lake in the Erie basin spilled 
 over Niagara Falls, and the three upper lakes poured their 
 waters in a wide torrent through the Ottawa River valley, 
 in Canada, into the Atlantic Ocean which by then had entered 
 and drowned the Gulf of St. Lawrence as far west as the 
 vicinity of Ottawa, Ontario. Some three thousand years 
 ago — perhaps about the time the camel caravans of King 
 Solomon were bringing copper ores to the smelters of the 
 great king at Exion-Geber and his argosies were sailing the 
 Red Sea, when the glamorous Queen of Sheba brought gold 
 and spices to the ruler of Judeah, when the people of Central 
 and South America were building great pyramid temples to 
 the Sun-God — a sluggish river crossing the flat lands now 
 covered by Lake St. Clair was quickened by flooding waters, 
 as the three upper great lakes deserted their eastern outlet 
 through Ontario and poured their waters southward through 
 the St. Clair and Detroit rivers, and the present Great Lakes 
 system was established. 
 
 This is no fantastic tale of idle dreaming; it is a sketch of 
 events in the Story of the Great Lakes — a romance of Nature's 
 slow, gradual change of the face of the continent, an Auto- 
 graph of Time which the lakes themselves in main part have 
 written— the Story of "NE-SAW-JE-WON," as the Ottawas 
 say, meaning The Waters That Run Down From Lake 
 Superior To The Sea. 
 
 10
 
 SETTING FOR lliL ICE-AGE DRAMA 
 
 THE SroRY oi THE Grl A I Laki£S is largely a story of the 
 Ice Age in North America, a period geologically recent, 
 which began only about a million years ago. But the 
 events of the preceding eons of geologic time — hundreds of 
 millions of years — when the forces of Nature were warring 
 over the tasks of building, tearing down and rebuilding the 
 rock formations of the continent, all played parts in prepar- 
 ing the stage for the drama of the ice invasion. 
 
 The Rock Formations and Pre-Glacial History 
 OF THE Great Lakes Region 
 
 In the days when the Earth was young and turbulent, the 
 Great Lakes region was the basin-shaped floor of the sea 
 bordering a shield-shaped mass of igneous rock lying to the 
 north — the initial North American continent. Several times 
 in the eons that passed, as the Earth settled down and the 
 continents became stable, the borders of this land were up- 
 lifted to mountain height, only to be worn down almost to sea 
 level during long periods of quiescence. Finally a great con- 
 vulsive, though slow, earth movement lifted to Alpine heights 
 a mountain range extending from Minnesota and Wisconsin, 
 in a northward-bearing arc, to the Laurentian Highland in 
 Canada and the Adirondacks in New York. The several 
 uplifts, whether slow or violent, changed the rocks so that the 
 borders of the continent came to be a region of igneous and 
 metamorphic rocks — granites, gneisses, schists, lavas, slates, 
 and bedded rocks which were crumpled and folded. In the 
 west these mountains have long since been worn away almost 
 to their roots, leaving only rugged uplands in the highlands 
 surrounding Lake Superior. 
 
 When earth forces brought uplifts of this vast area, they 
 were accompanied by local downwarps or flutings of the sur- 
 
 11
 
 oo 
 
 uiO 
 
 o 
 
 cS S Q (/) O O ol 
 
 HH '^ 
 
 M '^ 
 
 12
 
 ROCK FORMATIONS AND PRE-GLACIAL HISTORY 
 
 face. One of these depressions, produced late in this early 
 history, in time became the elongated curved basin of Lake 
 Superior. Another much older depression, centering in the 
 Southern Peninsula of Michigan and there more or less circu- 
 lar in shape, extended eastward in a rising scoop-like trough 
 to east-central New York. This depression became the basin 
 in which later invading seas deposited a great series of layered 
 formations, one above another, made of the sediments weath- 
 ered and eroded from the ancient rocks of the adjacent 
 uplands. Slow earth movements caused sea after sea to enter 
 and withdraw or be spilled from this basin, each sea being 
 smaller than and within the boundaries of its predecessor, and 
 each leaving layers of accumulated sedimentary material to be 
 buried — in the central area of the basin — by the deposits of its 
 successor. These sediments were compressed and hardened into 
 rock — sandstones, limestones, shales, rock salt and gypsum. 
 Coal beds, formed from the abundant vegetation which grew 
 in the marshes associated with the later seas, were inter-bedded 
 with the upper rock formations. 
 
 With the withdrawal of the last sea the land was elevated, 
 and a long period of weathering and erosion followed. The 
 highest portions of the bedded rocks around the rim of the 
 scoop-like basin wore away first, bevelling the edges of the 
 basinward-sloping rocks but not disturbing the lower portions 
 in the interior of the depression. Thus developed a series of 
 gigantic "rock bowls" — one within another — occupying the 
 basin. They are like a great nest of mixing bowls with lips to 
 the east. Some of the rock layers are hard and resistant to 
 weathering, others are soft and easily eroded; hence in time 
 the once-beveled edges of the resistant sandstones, limestones 
 and dolomites came to have the general appearance of a series 
 of parallel, concentric, stone "ramparts" with steep outward- 
 facing exposures and gentle inner slopes toward the basin. 
 These are separated by the depressions worn in the softer, 
 less resistant layers — the shales, salt and gypsum beds. Where 
 
 13
 
 NE-SAW-JE-WON 
 
 these soft beds are deeply carved and gouged out along their 
 exposures they may be likened to "moats" between the ram- 
 parts of harder rock. 
 
 Without going into detailed descriptions of each set of rock 
 bowls, let us rather consider their relation to the development 
 of the basins of the Great Lakes. As flowers, trees and people 
 have distinctive family names, so names have developed to 
 designate the rock formations. English geologists first studied 
 the sedimentary rocks in England and Wales, and the names 
 given the formations there have now been applied all over the 
 world to rocks which have the same relative positions and are 
 similar in character and in the life records or fossils contained 
 in them. The lowest and oldest of the sedimentary rocks 
 known to the early geologists were named Cambrian, from 
 Cambria in Wales where they were first studied. For con- 
 venience, all the older igneous and metamorphic rocks are 
 grouped as pre-Cambrian. Above the Cambrian, in parts of 
 North America but not in Europe, is the Ozarkian, named 
 from the Ozark Mountains; the next set of higher and younger 
 rocks is the Ordovician, named from an ancient tribe of 
 Wales; over the Ordovician rocks are the Silurian, also named 
 from an ancient tribe of Britons that lived in Wales; then 
 come the Devonian, commemorating Devon in England; and 
 above these are the Carboniferous rocks — the Mississippian 
 and the overlying Pennsylvanian. (Figure 1.) 
 
 Insofar as the Great Lakes are concerned, the important 
 facts about the rocks are their arrangement and position and 
 their different degrees of hardness. The pre-Cambrian rocks, 
 which are hard and resistant to weathering, are downwarped 
 to form the basin of Lake Superior. The Cambrian is a very 
 resistant, coarse sandstone underlying the Ozarkian sandy 
 dolomite, dolomitic sandstone, and dolomite. The thin edge 
 of the Cambrian or Lake Superior sandstone, which once 
 rested upon the pre-Cambrian rocks, has been weathered away 
 until now its northern edge stands as the outer rampart of red, 
 
 14
 
 ROCK FORMATIONS AND PRE-GLACIAL HISTORY 
 
 Photo by Michigan Deparlmcnt of Comervation 
 
 PLATE 1.— "PICTURED ROCKS" RAMPART OF CAMBRIAN 
 SANDSTONE 
 
 SOUTH SHORE OF LAKE SUPERIOR; NIPISSING AND MODERN LAKES. 
 
 gray and white sandstone, rising majestically two hundred 
 feet above Lake Superior, facing the moat of the Superior 
 basin. It is the most battlcmented of all the ramparts, and on 
 it Nature has painted her "Pictured Rocks" and carved archi- 
 tectural designs that delight and awe the beholder. We can 
 follow this Cambrian rampart from Sault Stc. Marie to the 
 eastern half of the Keweenaw Peninsula,''" and from east of 
 Marquette we can trace it southward into south-central 
 "Wisconsin, where it swings westward around the old, igneous 
 land-mass of central Wisconsin. Short streams entering Lake 
 Superior from the south leap over the edges of the sandstone 
 
 *The sandstone in the basin of Keweenaw Bay, which forms tlie rampart alonj; its shore 
 and east nearly to Marquette, may be of pre-Cambrian age. (Editor.) 
 
 H
 
 NE-SAW-JE-WON 
 
 photo by Michigan Department of Conservation 
 
 PLATE 2.— FALLS OF TAHQUAMENON RIVER 
 
 LARGEST FALLS WEST OF NIAGARA 300 FEET WIDE, FALLING OVER A 
 
 LEDGE OF CAMBRIAN SANDSTONE. 
 
 into Lake Superior or reach the lake in cascading beauty of 
 misty falls over the fortressed cliffs. The tranquil 300-feet- 
 wide Tahquamenon River falls in majestic grandeur over 
 ledges of red-brown sandstone at the Upper Falls, rushes 
 through a gorge it has cut in the rock to the ledges of the 
 Lower Falls, and then winds again tranquilly on to the lake. 
 Other streams have cut short gorges in the sandstone, but the 
 positions of their falls near the lake are maintained and de- 
 struction of the falls is prevented by the layer of resistant 
 Hermansville (Ozarkian) limestone, which is the rim of the 
 next inner rock bowl. 
 
 Above and within the white, sandy Ozarkian dolomites and 
 limestones were deposited the lime muds which became the 
 hard, resistant limestones of the early Ordovician — the Black 
 
 16
 
 ROCK FORMATIONS AND PRL-GLACIAL HISTORY 
 
 River and Trenton limestones. The Menominee and White- 
 fish rivers cascade over the nortliern edges of these southward- 
 sloping rocks to reach Green Bay and Lake Michigan. When 
 the limestone-making sea became shallower, fine muds were 
 deposited, and through countless ages these also hardened to 
 rock — a soft shale. When exposed at the surface the shale did 
 not resist weathering but gradually was worn away to form 
 the moat behind the Cambrian-Ozarkian-early Ordovician 
 sandstone and limestone rampart. Today we find parts of that 
 moat occupied by Green Bay of Lake Michigan, by North 
 Channel and Georgian Bay of Lake Huron, and by the Lake 
 Ontario basin in the eastward extension of the Ordovician 
 rocks. 
 
 Following the time when the muddy seas of the late 
 Ordovician deposited muds that became the soft shales under- 
 lying the Green Bay-Georgian Bay-Ontario moat, came the 
 Silurian time of genial climates when in the warm clear seas 
 life was abundant. Shelled creatures of many kinds swam the 
 seas or crawled upon their floors, and corals and bryozoans 
 built great reefs. The shelled creatures and corals died, shells 
 and reefs w^ere broken and buried in lime mud, and through 
 long ages the muds hardened to limestone filled with the petri- 
 fied remains of a life long past. So hard and resistant to 
 weathering is this rock that it formed the next great encircling 
 rampart. This limestone is named Niagaran, because of its ex- 
 posure along Niagara River — particularly at the brink of Ni- 
 agara Falls. From western New York south of Lake Ontario, 
 the Niagaran limestone rampart extends northwesterly across 
 Ontario in a broad arc separating Georgian Bay from Lake 
 Huron, rises to the surface as Manitoulin and Drummond 
 islands, continues across the eastern half and forms the south 
 shore of the Northern Peninsula of Michigan (excepting St. 
 Ignace Peninsula) , then circles southward between Green Bay 
 and Lake Michigan along the Lake Michigan shore of Wiscon- 
 sin to the southern end of Lake Michigan, where it forms the 
 
 17
 
 NE-SAW-JE-WON 
 
 sill holding the waters of the lake in the basin. Where the 
 shales which underlie it are cut away, the Niagaran rampart 
 stands in places like a cornice, rather than with the fortress- 
 like character of the Cambrian sandstones ; but it is sufficiently 
 impregnable to have played a most important part in the 
 development of the lakes. The close of Silurian time was 
 marked by dry climates and by a shrinking sea from which 
 life almost departed and which left enormously thick beds of 
 salt and thinner beds of gypsum. 
 
 Then came a return of more genial climates, and a warm 
 sea — the Devonian — entered the lake region and left thick 
 sediments in the deep basin of the Michigan area. A part of 
 the Devonian record is in the limestone which makes the 
 rampart along the northern rim of the Southern Peninsula 
 of Michigan from the Traverse Bay area to Alpena, which is 
 submerged under Lake Huron, crosses Ontario and swings 
 back again into southeastern Michigan, northern Ohio and 
 Indiana, and which forms the western bowl in which the 
 thick soft shales of the late Devonian and early Mississippian 
 were deposited. These soft shales, together with the shales and 
 salt beds of the late Silurian, in time were carved out to form 
 the moat back of the Niagaran rampart, and in them the 
 channels of great rivers were cut — rivers which carved valleys 
 now filled by Lakes Michigan, Huron and Erie. 
 
 Above the thick shales of the lower Mississippian is a hard 
 sandstone overlain by limestone and gypsum beds. Parts of 
 the sandstone and limestone rims come to the surface near 
 Holland, Michigan, and also along the shore of Lake Huron 
 — around the "Thumb" of Michigan and along the opposite 
 shore of Saginaw Bay. The southern rims of these Mississip- 
 pian sandstone and limestone bowls are near the surface along 
 an arc extending from the Thumb through south-central 
 Michigan to Holland, and although inland, they played their 
 parts in the lake history. 
 
 Within the Mississippian bowl in Michigan is the set of
 
 ROCK FORMATIONS AND PRE-GLACIAL HISTORY 
 
 Pennsylvanian sandstones, shales and coal beds. These had 
 little to do with the story of the Great Lakes, except that a bit 
 of their eastern rim was cut into to form the southwestern end 
 of Saginaw Bay. 
 
 After Pennsylvanian time no seas entered the immediate 
 area of the Great Lakes, and for many millions of years Na- 
 ture was busy cutting, carving and wearing away the rocks 
 laid down in the region. The soft shales and salt beds were 
 eroded to form the wide moats, or trenches, between the more 
 resistant formations which made the escarpments, evidences 
 of the channels by which the seas had entered the region were 
 obliterated, and a thick soil cover was developed. However, 
 Nature was very busy building up the rest of the continent 
 of North America — folding the Appalachians to mountain 
 height, wearing them down to almost a plain, then lifting 
 them again in a wide plateau which since has been carved to 
 the Appalachian Mountains as we know them now. The Great 
 Plains were built up, the Sierras and then the Rockies uplifted, 
 and the mountains of the ancient pre-Cambrian area about 
 Lake Superior were worn down. In the entire lake region we 
 have no rock records of this time — known as the Mesozoic 
 and Cenozoic eras, yet we know that with the general uplift 
 of the continent this region was lifted much higher above 
 sea level than it now stands. 
 
 The force that lowered the northern part of the continent 
 and changed the ancient river valleys to lake basins started 
 its work about a million years ago when a climatic change 
 took place. The winters became not so much colder, but 
 longer — so long that the snows of one winter were not melted 
 by the summer sun before another winter set in. This time 
 period we know as the Pleistocene, the age of the great con- 
 tinental glaciers which build the final rock record in the Great 
 Lakes region. It ended when the ice had melted to the small 
 remnants of the Greenland ice cap. Geological formations 
 now in the making arc known as Recent. 
 
 19
 
 NE-SAW-JE-WON 
 
 FIGURE 2.— GLACIAL MAP OF NORTH AMERICA 
 
 SHOWING THE MAXIMUM EXTENT OF THE ICE SHEETS AND THE SEVERAL 
 CENTERS OF ICE ACCUMULATION. 
 
 From U. S. Geological Survey. 
 
 The Glacial Period and Its Records 
 During early Pleistocene time, in the highlands about Hud- 
 son Bay snow accumulated throughout hundreds of years 
 and became packed to ice so thick that it pushed outward by 
 
 20
 
 THE GLACIAL, IMRIOD AND ITS RKCORDS 
 
 its own weight, just as a mass of clay or dough piled on a 
 board spreads outward from its thick central mass. Once 
 started to move, tiie mass of snow-ice became a glacier, which 
 is estimated to have been from two to six miles thick and 
 which reached a maximum extent of approximately 1600 
 miles from its center to the Ohio Valley. Lour times during 
 that million years the ice advanced over and retreated from the 
 continent. Each advance had some effect upon the lake re- 
 gion, but it is only with the last advance — the so-called Wis- 
 consin glaciation — that we are particularly interested. This 
 last advance obliterated or buried much of the record of the 
 earlier invasions, although it did not quite reach to the Ohio 
 valley, as the preceding Illinoian invasion had done. 
 
 Once started, the ice moved slowly, relentlessly southward 
 from the Hudson Bay area. Its freezing grip clutched the 
 loosened rock ledges and plucked them away; it crushed and 
 scooped up the surface debris, absorbing boulders, sand and 
 clay into its mass, and slowly carried forward its load of rock 
 materials to deposit them far from their source. -It used peb- 
 bles, cobbles and boulders frozen in its base as great files, rasps 
 and plough points to scratch and groove the surfaces of the 
 bed rock over which it passed; or with fine rock and clay it 
 scoured and polished these surfaces and rounded and polished 
 the boulders and pebbles within its mass. By the scratches, 
 grooves and polishings on rock ledges, we know in what di- 
 rections the ice moved. At times this last great glacier, like 
 the others before it, melted faster than it pushed forward, so 
 that the southward movement was somewhat pulsating; but in 
 the main, for thousands of years it moved steadily southward, 
 carting along within its mass unmeasured quantities of rock 
 debris which it had taken from the lands to the north. When 
 it reached the area of the Great Lakes, tongues of ice entered 
 the river valleys in the ancient rocky moats and there became 
 thicker and moved more rapidly. These river valleys were in 
 the soft shales, hence the ice gouged and furrowed them; it 
 
 21
 
 NE-SAW-JE-WON 
 
 FIGURE 3.— GLACIAL MAP OF THE GREAT LAKES REGION 
 
 SHOWING THE DIRECTIONS OF MOVEMENT OF THE SEVERAL GLACIAL LOBES 
 AND THE POSITIONS OF THE ICE BORDER AT SUCCESSIVE STAGES IN THE 
 
 RETREAT. 
 
 From Frank Leverett and F. B. Taylor. 
 
 deepened and widened, but did not carve them to the U- 
 shaped valleys which distinguish the action of glaciers in high 
 mountains. These tongues or lobes of ice in the valleys that 
 now are the basins of the Great Lakes acted almost as inde- 
 
 22
 
 THH GLACIAL PERIOD AND ITS RECORDS 
 
 pendent glaciers, the ice advancing outward from their own 
 axes or centers. Thus the ice in the Lake Michigan basin 
 moved not only southward with the general movement of 
 the glacier but also radially from the central axis, southwest- 
 ward and southeastward, toward the edges of the basin. The 
 ice lobes in other basins had similar movements, which are 
 revealed in the rather complicated directions of the scratches, 
 also by curious features carved in the bedrock and by under- 
 lying deposits of earlier glaciations. 
 
 Once past the old river valleys the ice fronts again united, 
 and the glacier — shaped somewhat like a huge cauliflower 
 with its stem to the north — moved southward almost to the 
 Ohio River. Its extent is marked by the line of hills, known 
 as terminal moraine, extending irregularly eastward from 
 Shelbyville, Illinois, to southern Ohio, thence into north- 
 western Pennsylvania, and from there southeastward to and 
 across Long Island. The advance was stopped by a slow 
 climatic change which caused the ice to begin a lingering, 
 halting retreat, marked by occasional readvances of the ice 
 front, but nevertheless a continuous withdrawal northward. 
 When the retreating ice front reached the ancient river valleys 
 the glacier once again assumed the tongue or lobate character 
 — thicker in the valleys and thinner on the uplands — each lobe 
 again with the characteristics of an essentially independent 
 glacier. 
 
 The records of the retreat are similar to the records of re- 
 treat of living glaciers, easily studied in the Alps and in the 
 high Sierras, which furnish the clues to the work of the con- 
 tinental ice sheet. The records are mainly in long lines of 
 hummocky hills — moraines — of rock debris which the ice de- 
 posited as it melted. When the rate of forward push of the 
 ice was equalled by the rate of melting at its border, the ice 
 front remained stationary for many — probably hundreds — 
 of years, and the rock waste brought from the north settled 
 out of the melting ice at its edges, accumulating there like 
 
 23
 
 NE-SAW-JE-WON 
 
 debris on a city dump. Obviously, this material is a collection 
 of all sorts of unrelated odds and ends of rock material from 
 the varied surfaces over which the ice had passed. The melt 
 water sorted out some of the debris and carried it away from 
 the ice front, building up deposits called outwash plains or 
 aprons, the coarser gravel being left near the moraines and 
 the finer gravel, sand and silt being carried farther away. 
 The moraines may be likened to entrenchments thrown up 
 for protection by the retreating ice in the warfare between 
 heat and cold. They mark the lines of halt and reinforcement, 
 followed by giving-way and further retreat, as the warming 
 climate slowly forced the glaciers from the continent. A rapid 
 retreat, when the forces of heat were great and when melting 
 was more powerful than the forward push, caused the rock 
 debris to be deposited in gently undulating plains of com- 
 mingled sand, clay and stones called till. These deposits, known 
 as ground moraine or till plains, are similar on a large scale to 
 the dusty, clayey deposit left on the surface after a persistent 
 winter snowbank has melted. Formation of the till plain was 
 stopped at each halt, as the ice built another backstep moraine. 
 Long roughly parallel lines of morainal hills, stretching from 
 Pennsylvania to Illinois, mark the retreat of the Wisconsin 
 glaciation in the Ohio valley region. But when the ice had 
 retreated to the Great Lakes area the valleys of the ancient 
 river systems again determined the shape of its front; again 
 the ice assumed lobate form, the lobes acting as independent 
 glaciers in the Lake Michigan, the Huron-Erie and the 
 Superior basins. The moraines which mark the halts of 
 these glacial lobes are festooned about the basins in lines of 
 hummocky hills which roughly parallel the borders of the 
 present lakes. In time, as melting progressed, the lobes came 
 to be more completely separated, so that distinct glaciers 
 occupied the basins of Lake Michigan, Green Bay, Lake Erie, 
 Lake Huron, Saginaw Bay, and finally the Ontario basin. In 
 the Lake Superior region the ice probably divided into lobes 
 
 24
 
 THE GLACIAL PLKIOD AND ITS RLCORDS 
 
 on either side of Keweenaw Peninsula. In places the moraines 
 of adjacent lobes were pushed together, making a jumble of 
 high hills such as the scenic Irish Hills of southeastern Michi- 
 gan and the high hills of the northern part of the Southern 
 Peninsula. These morainic hills, with their beautiful lakes 
 of ponded waters and with clear streams rushing down their 
 slopes, give to the glaciated region its varied and picturesque 
 beauty. Other parts of the country have hills carved from 
 the bed rock of the region, but the glaciated district, particu- 
 larly in Michigan, has also hills built by a plastering of rock 
 waste scraped off Canada, transported and dumped by the ice. 
 The ice in the Saginaw Bay lobe melted faster than the ice of 
 the Michigan and Huron-Erie lobes, because it was thin over 
 the rim of the Marshall (Mississippian) sandstone — one of our 
 old "rock bowls." Its retreat was rapid and marked by brief 
 halts, with the result that the moraines of that lobe are 
 grouped in a necklace arrangement of pendant festoons about 
 the bay — narrow belts of low rolling hills with broad flat 
 valleys (outwash plains) between, in contrast to the high 
 sharply-hilled moraines of the other glacial lobes. In other 
 states of the glaciated area and in the Northern Peninsula of 
 Michigan much of the bed-rock is exposed at the surface or 
 the drift is thin, but in the Southern Peninsula the burial 
 cover of glacial drift is so thick that bed-rock appears at the 
 surface in but few places. Hence secrets of mineral wealth in 
 the underlying rocks have been preserved until mechanical 
 ingenuity made it possible to drill through the thick cover 
 of drift. 
 
 High conical gravelly hills mark the sites of water falls 
 where streams flowing in channels or tunnels high in the ice 
 fell over its edge and piled their rock debris in dumps at the 
 foot of the falls. Such hills, known as kames, standing alone 
 or in groups of several on the till plain or in the terminal 
 moraine, may be easily recognized by their form and by their 
 water-sorted contents where these are exposed in excavations. 
 
 2J
 
 NE-SAW-JE-WON 
 
 In the early-inhabited parts of the glaciated district they were 
 used for burial places, as generally the soil cover was thin and 
 their gravel content provided good drainage. In many places 
 they furnish gravel and sand for road building and other con- 
 struction. Long narrow hills that look like abandoned rail- 
 way embankments mark the sites of walled or tunnelled chan- 
 nels of streams which flowed upon, within, or under the ice. 
 These stream channels became choked with rock debris, and 
 when the ice melted the water-sorted material settled to the 
 land surface, its sides assuming characteristic steep angles of 
 repose. These sinuous hogback ridges, known as eskers, may 
 be from a few feet to more than a hundred feet high and 
 from a fraction of a mile to many miles long. They are on 
 the till plains and in the moraines. 
 
 Other strange products of glacial building are drumlins, 
 curious hills shaped like inverted canoes, found on the till 
 plains, aligned in the direction of the ice movement. Some 
 drumlins, such as those on the limestone Cheneaux Islands, 
 and the lenticular hills in the drumlin area of Grand Traverse, 
 Michigan (found on excavation to have cores of shale covered 
 with a plastering of pebble-set clay), evidently were "shaped 
 into drumlinoid form by the ice passing over them"; some are 
 sculptured till; and others are a special form of ground mor- 
 aine — mounds of glacial till with elliptical bases. Drumlins 
 may be from fifty to three hundred feet high and from one- 
 fourth mile to one and one-half miles long; many of them are 
 steepest on the end facing the direction from which the ice 
 came. The exact manner of origin of these remarkable hills is a 
 matter of much speculation. They are usually arranged in 
 fan-shaped groups; and it is believed that in some way they 
 were carved from old till by readvance of local ice lobes, or 
 were accretions of till beneath the ice along margins of broad 
 lobes — perhaps in long crevasses, or are hills carved in the 
 bed-rock by the advancing glacier and coated over with stony 
 clay left by melting ice. Excellent examples of drumlins may 
 
 26
 
 THE GLACIAL PLRIOD AND ITS RLCORDS 
 
 be seen near the southern end of Green Bay, in Wisconsin; in 
 Dickinson, Marquette, Deha and Menominee counties, the 
 Les Cheneaux Lsland area, and in tlie Grand Traverse region, 
 in Michigan; as well as in western and central New York. 
 
 All this plaster of rock waste quite foreign to the forma- 
 tions on which it lies — these moraines, kames, eskers, drum- 
 lins, outwash plains, till plains, mixed accumulations of all 
 sorts, sizes and shapes of rock fragments — limestone, sand- 
 stone, jasper, granite, gneiss, chunks of copper, iron ore, rare 
 flakes of gold, even a few diamonds, beds of clay, sand, gravel 
 — spread over the glaciated region, is collectively known as 
 drift, because early geologists believed it to have been spread 
 by drifting currents and icebergs in an ancient sea. Its thick- 
 ness varies widely; in some places it is very thin or entirely 
 lacking and in others it is from 800 to 1,200 feet thick. 
 
 A large area in southwestern Wisconsin was never covered 
 by the ice. Not because it was too high, but for some other 
 reason, the ice deployed around it, leaving the famous Drift- 
 less Area in which the beautiful and interesting Dells of the 
 Wisconsin River have been cut by that stream in the red- 
 brown Cambrian sandstones. A small peak of rock standing 
 like an island above a glacier is known by the Eskimo name 
 "nunatak." Around such a nunatak in Ontario the ice de- 
 ployed in its forward march and formed the Huron and Erie 
 lobes, and in the retreat the nunatak separated these lobes. 
 Highlands in the Northern Peninsula once covered by the ice 
 became nunataks for a time during the retreat. 
 
 As the glacier retreated northward, the melt water from 
 the ice escaped in broad channels leading southward to the 
 Ohio River and thence to the Mississippi. These channels, 
 now the wide flat valleys of too-small rivers, furnisjied the 
 routes for man-made canals in the heyday of canal building 
 in Ohio. The great volume of glacial water reached the Ohio 
 and vastly increased the size and activity of that river. Ad- 
 vance of the ice had pushed the river southward in the vicinity 
 
 17
 
 NE-SAW-JE-WON 
 
 of Cincinnati, but with removal of the ice barrier the river 
 returned to its former course. 
 
 The Records Made by Rivers and Lakes 
 
 Nature today continues to make the same sort of records 
 she has always made on the face of the earth. As the work 
 of living glaciers supplies the key to knowledge of the ancient 
 ice invasions, so does the work of modern streams and lakes 
 furnish the key to the records made by rivers and lakes of 
 the past. Each river and lake writes its own life-story. Start- 
 ing as small rills or brooks, rivers increase in size as they ac- 
 quire tributaries. At the same time they use tools found in 
 their paths or supplied by tributaries — cobbles, pebbles, 
 gravels, and even huge boulders in flood times — to cut and 
 carve their channels deeper. Having deepened their channels 
 to the limit of their power, they wear away their banks. The 
 net result is the production of a valley, narrow near the 
 source of the stream and widening into a broad flaring "V" 
 toward the outlet. The cross-section of the valley is also 
 V-shaped, being a sharp V near the headwaters and almost 
 flat near the mouth. Tributary streams enter with their cur- 
 rents directed downstream, so that in time the river system 
 has the familiar "tree," or dendritic, pattern. The streams in- 
 crease in length by headward cutting (even when the source 
 is in a lake, the lake is drained eventually) and by building 
 deltas at the mouth and then cutting across them. As the 
 river grows old, it will have drained the lakes in its course and 
 built a wide flat on which it swings lazily and muddily from 
 bank to bank, like the Mississippi. By contrast, in the areas 
 which have been glaciated the drainage is poor and hap- 
 hazard, for pre-glacial stream courses have been more or less 
 filled with drift, the streams diverted, and waters ponded to 
 form lakes and swamps. Tributaries may enter the main 
 stream at any angle, valleys may be wider near the headwaters 
 than near the mouth, small streams may occupy much-too- 
 
 28
 
 RECORDS MADL BY RIVHRS AND LAKES 
 
 wide valleys; or valleys which have all the appearance of river 
 vallcvs may have no streams in them at all. In places beds of 
 rounded gravel are lett to mark the channels of departed 
 streams; in other places rocky ledges show that they have 
 been scoured by tools carried by rushing river waters. In a 
 word, major streams in a glaciated region do not conform to 
 any pattern; their courses are determined by the manner of 
 deposition of the drift-cover rather than primarily by the 
 slope of the land and the character of the bed-rock surface. 
 Actually, many of the streams once flowed in directions op- 
 posite to the courses they now take, as, for example, Maumee 
 River which now enters Lake Erie at Toledo: its drainage 
 pattern is more like a double anchor than like a tree; its val- 
 ley widens toward the headwaters which once flowed south- 
 westward down the channel of the Wabash. A dry river 
 channel now separates the Wabash and the Maumee near 
 Fort Wayne, Indiana — a channel which has its place in the 
 history of the Great Lakes, as well as in the history of the 
 migrating Indians who used it as a trail and of the white men 
 who there built a fort to guard the way to the west. The life 
 story of most of the streams entering the Great Lakes is as 
 varied as is the tale of the lakes. 
 
 Present-day lakes are making shore lines, beaches, strands 
 and ridges; waves and currents wash sediments onto and along 
 their shores; deltas are being built at the mouths of streams, 
 or the mouths are being filled by wave and current action 
 which curves the lake beaches into them; sands along the 
 shores are rounded and etched to grains of distinctive charac- 
 ter and are sorted and piled by the wind into heaps called 
 dunes; pebbles shifted along the shores by currents and waves 
 become flattened, showing their beach origin in contrast to 
 the rounded pebbles shaped by rolling along in streams. (Such 
 flattened pebbles on a beach are known as shingle.) The 
 
 29
 
 NE-SAW-JE-WON 
 
 Photo by Michigan Department of Conservation 
 
 PLATE 3.— BEACH ON MACKINAC ISLAND 
 
 LOOKING SOUTH FROM BRITISH LANDING. SHOWS CHARACTERISTICS OF A 
 
 MODERN BEACH. STEP NOTCHES IN BACKGROUND ARE SHORES OF THE 
 
 NIPISSING AND ALGONQUIN LAKES. 
 
 shore lines of lakes are being straightened to smooth curves, 
 as waves and currents build bars, hooks and spits across the 
 coastal indentations, making lagoons which in time become 
 swamps and then flat muck-lands. Sand and gravel are left 
 along the lake beaches, but the finer sediments are carried 
 farther from shore, and the very finest muds are deposited in 
 deep water. The manner of settling of these most-finely- 
 ground muds supplies an interesting geological clock by which 
 to actually measure in years the rate of accumulation of these 
 sediments; and from their thickness can be derived an ap- 
 proximate age for the lake in which they were deposited. In 
 the summer time when sediments are being washed into the 
 lake, the coarser of the fine muds settle to the bottom rather 
 
 30
 
 RECORDS MA PL BY R1\'LRS AND LAKLS 
 
 rapidly and build a layer of light-colored sediments. Then in 
 the winter time when ice covers the lake or the land is so 
 frozen that little or no sediment is washed from it, the very 
 fine particles of silt and minute organic matter, which re- 
 mained in suspension in the water all summer, gradually 
 settle to the bottom in the cold quiet water and build a thinner 
 layer of dark-colored sediments on top of the thicker summer 
 layer. Such seasonal layers of alternating fine dark -colored 
 and coarser light-colored clays are known as varves. It is 
 evident that if a section cut through layers of varved clays 
 to the original bed of a lake can be examined, the number of 
 seasons the lake lived can be determined, just as the age of a 
 tree is determined by the seasonal rings of wood that it ac- 
 quires. If a lake exists long enough all depressions of its bot- 
 tom will be filled to a common flat surface. At times the 
 level of a lake may be raised, its area become larger, and its 
 storm waves more powerful. The waves bite into the beaches, 
 notching them on the lakeward side, cut into high lands along 
 its shores, and make water-worn cliffs. If the higher stage 
 exists long enough the lake may completely destroy the shore 
 forms made at a lower level. If the borders of the lake are 
 resistant rocky cliffs, the waves cut grottos and sea caves in 
 them and pound the loosened debris on the shore into a narrow 
 rocky beach. Outlets of lakes also have their distinctive 
 characteristics. The lake beaches curve into the outlet and 
 disappear in the channel, as the outlet assumes the character 
 of a river and slopes away from the beach lines; thus old 
 abandoned outlets can be identified. 
 
 If the lake dries up or is drained away all these records — 
 beaches, strands, dunes, shore cliffs, sea caves, grottos, varved 
 clays, flat lake-beds of sand and clay — are left high and dry, 
 showing where the lake once was and revealing its history. 
 The strength of these features indicates the length of time 
 the lake endured. Obviously a short-lived lake would make 
 weak, ill-defined shore features, whereas a long-lived lake 
 
 31
 
 o 
 o 
 < 
 u 
 
 X 
 u 
 
 Q 
 Z 
 < 
 
 w 
 
 W 
 < 
 
 < 
 
 < 
 
 o 
 w 
 
 H 
 
 Ph 
 
 O 
 
 
 32
 
 THi: GLACIAL LAKES 
 
 would cut and build strong and pronounced beaches, shore 
 cHflPs and terraces. It is possible that many lakes once existed 
 of which we shall never have knowledge, for they left records 
 so weak and faint as to be now illegible. At any given level 
 of a lake the features of its shores and beaches must have been 
 horizontal and all related to that elevation. If the lake be- 
 comes smaller and remains long enough at a lower level, new 
 shore features will be made at that elevation; if it becomes 
 larger the rising waters wash over the older shore lines but do 
 not always destroy them. In fact, if the waters rise rapidly 
 and the lake becomes deep, old shore features of a lower level 
 may be well preserved; and if the new higher lake persists 
 long enough, these features may be buried by its varved clays. 
 Changes of lake level make all sorts of complications in the 
 records, but because shores are horizontal when made, most 
 of the records can be deciphered. 
 
 It is from such records of glaciers, rivers and lakes, some 
 simple, others complicated, that we have been able to read 
 and learn of the development of the Great Lakes. 
 
 Lake Maumee — The First of the Glacial Lakes 
 
 When the ice had melted so far north that its front stood 
 north of the drainage divide and the land sloped toward the 
 ice, streams of melt water could no longer flow freely south- 
 ward, hence the water collected in front of the ice in long 
 narrow pools back of the bordering moraine. From the rec- 
 ords such as those described, we know that the earliest glacial 
 pools which formed along the edge of the ice lobe in the Erie 
 basin were in northwestern Ohio. When the ice had melted 
 far enough, several pools united to form a narrow crescent- 
 shaped lake around the front of the Erie ice lobe. Thus was 
 born the first of the great lakes — the ancestor of Lake Erie. 
 Faint beaches were made by these early pools of melt-water, 
 but the waters rose steadily and finally formed a strong beach 
 at the highest level the lake reached, about 230 feet above tlie 
 
 33
 
 NE-SAW-JE-WON 
 
 present level of Lake Erie. At this stage the over-flow waters 
 escaped over a "col" (low place between hills) in the im- 
 pounding moraine and flowed from the lake-basin south- 
 westward, past the site of Fort Wayne, to the Wabash River 
 which had been one of the escape channels for the melt-water 
 before the lake was formed. Thus the first outlet of the Great 
 Lakes was via the Wabash and Ohio rivers to the Mississippi 
 and the Gulf of Mexico. The Maumee River now flows into 
 Lake Erie over the bed of this ancient lake, hence its name — 
 Lake Maumee. (Figure 4.) 
 
 Early Lake Chicago; Lake Jean Nicolet 
 
 Shortly after the formation of the first Lake Maumee, 
 another long narrow lake began forming at the foot of the 
 ice lobe in the Lake Michigan basin, between the retreating 
 ice and the morainic barrier. This was the beginning of 
 glacial Lake Chicago, the ancestor of Lake Michigan. Its out- 
 let was through the lower channel of the present Des Plaines 
 River, into the Illinois, and thence to the Mississippi and the 
 Gulf of Mexico. Probably only a little later two small lakes 
 formed at the southern end of the ice lobe in the Green Bay 
 basin. The outlet of one of these was southward to Rock 
 River and of the other southwestward to Wisconsin 
 River, thence to the Mississippi and the Gulf. These lakes 
 later united, forming glacial Lake Jean Nicolet which is of 
 interest but of relative unimportance. It did not last long 
 enough to make strong shores as an independent lake, for it 
 soon merged with Lake Chicago, when the retreating ice 
 opened passage to that lake. 
 
 Very much later a similar crescent-shaped lake was formed 
 around the western end of the Superior ice lobe. It was known 
 as glacial Lake Duluth, the ancestor of Lake Superior, and 
 discharged southward through St. Croix River to the 
 Mississippi. 
 
 From these four small crescent-shaped glacial lakes, ini- 
 
 34
 
 THE GLACIAL LAKES 
 
 tially all outside the basins of the present lakes and all dis- 
 charging southward to the Mississippi and the Gulf of Mexico, 
 grew a series of lakes "which for size and complicated history 
 is not known in any other part of the world." The total area 
 which at some time has been covered by waters of these 
 glacial lakes is considerably greater than the area of the pres- 
 ent Great Lakes (now about 95,000 square miles), although 
 the entire area submerged was not covered at any one time. 
 Only one glacial lake was larger — Lake Agassiz, of which 
 Lake W'innepeg is a remnant. Although it once covered 1 10,- 
 000 square miles, its history is very simple. It also was formed 
 in front of an ice barrier during the retreat of the last glacier 
 — the Keewatin ice sheet which late in the retreat of Wisconsin 
 glaciation had pushed southward from a center west of Hud- 
 son Bay and had reached south as far as Des Moines, Iowa, 
 over-riding the deposits of its earlier neighbor — the Patrician 
 lobe of the Labrador ice. (Figure 2.) The Keewatin 
 glacier persisted for some time after the formation of the in- 
 cipient Great Lakes, thus Lake Agassiz came into existence 
 long after the Great Lakes were well established. Its outlet 
 was to the Mississippi before establishment of the present 
 drainage. The bed of Lake Agassiz now makes the wheat 
 lands of the northwest, in Minnesota, North Dakota, Mani- 
 toba and Saskatchewan. 
 
 The accompanying maps show the manner of development 
 and the changes in the lakes more graphically than words can 
 describe. Figure 1 shows the distribution of the rock forma- 
 tions which determined the location of the lake basins. Figure 
 2 shows the areal extent of and the centers of accumulation 
 of the ice sheets which covered the northern part of North 
 America during Pleistocene time. Figure 3 shows the direc- 
 tions of movement of the ice in the glacial lobes which oc- 
 cupied the several lake basins and the positions of the ice 
 border at successive stages in the retreat. The other maps, in 
 order, show the various strand lines and outlet streams of the 
 
 3J
 
 THE GLACIAL LAKES 
 
 lakes, and also the probable positions of the ice front as 
 marked by the terminal moraines made by the several lobes. 
 Glacial Lake Maumee (Figure 4) was curiously shaped, 
 with long narrow arms extending around the edge of the Erie 
 ice lobe and a funnel-Hke outlet southwestward to the Wabash 
 River. Along tiie bordering moraine are the lake beaches, 
 sloping eastward into the flat bottom of the old lake. The ice 
 front of that time is marked by the line of hills known as the 
 Defiance moraine (named from Defiance, Ohio), which 
 swings around the position marking the edge of the Erie lobe 
 from Ohio into Michigan. Where the lake bordered the ice 
 the moraine was deposited in the waters of the lake. 
 
 The Second Stage of Lake Maumee 
 
 When the ice retreated from the Defiance moraine, it 
 opened a northern outlet near Imlay City, Michigan, thirty- 
 five feet lower than the Fort Wayne outlet. The waters of 
 Lake Maumee then abandoned the Fort Wayne outlet and 
 flowed in an arc across the Thumb of Michigan, past Flint and 
 Durand, along the edge of the Saginaw ice lobe and into 
 Grand River. (Figure 5.) Before that time Grand River 
 probably had been only a trickling stream in a crease in the 
 moraine. The change in outlet started the second and lowest 
 stage of Lake Maumee, which lasted long enough for the lake 
 to build typical beaches and shore formations, as it had done 
 at the higher level. But from this time on the story of the 
 lakes becomes very complex. Retreats of the ice front opened 
 lower outlets and changed the direction of drainage discharge 
 from the lakes; re-advances of the ice raised the level of the 
 waters, closed older outlets and opened new ones. Almost 
 every oscillation of the ice front was of a duration long 
 enough for the lakes to produce their characteristic records. 
 By patient search many of the old strand lines have been lo- 
 cated, even though rising waters destroyed much of the 
 
 37
 
 NE-SAW-JE-WON 
 
 evidence during the glacial time, and wind, weather and man 
 have obliterated much of the record since. 
 
 The Third Stage of Lake Maumee 
 
 From this second or lowest stage of Lake Maumee, the 
 lake level was raised about twenty-five feet — almost to the 
 level of the Fort Wayne outlet — by a re-advance of the 
 
 Grassmere I 
 635-640 I Lake Elkton 
 Elkf-on ((formerly Lundy) 
 3ei5-620 I 
 
 Highest 5f Clair and Rouge 
 Lowest St Clair and 
 
 Lake Erie 
 
 Lake Erie.SdO-ssot^KS) 560i during 
 Low level dunng K(rkfield '-^^^ N, pissing 
 stage of Lake Algonquin 
 
 FIGURE 6.— DIAGRAM SHOWING WATER LEVELS OF THE 
 VARIOUS STAGES OF LAKES IN THE ERIE BASIN 
 
 FROM THE FIRST LAKE MAUMEE TO THE PRESENT LAKE ERIE. (OLDEST AT 
 
 LEFT. BEACHES SUBMERGED BY LATER EXPANSION OF THE PONDED WATERS 
 
 INDICATED BY CROSS-HATCHED PATTERN.) 
 
 After Leverett and Taylor. 
 
 glacier, which moved westward up the slope of the highlands 
 of the Thumb. The ice front finally rested along the east side 
 of the Imlay outlet channel and there built a moraine which
 
 T H li GLACIAL LAKES 
 
 crowded the channel westward. In this stage the lake reached 
 its greatest extent. (ligure 5.) Curiously, it was lower than 
 the hrst Lake Maumee but higher than the second, and 
 stretched from Fort Wayne, Indiana, northward to Imlay 
 City, Michigan, and eastward to Girard, Pennsylvania. The 
 outlet continued through Grand River to the small Lake 
 Chicago in the Michigan basin, and thence to the Mississippi. 
 The ice front extended from the vicinity of Detroit across the 
 basin of Lake Erie, at a distance of forty or fifty miles east of 
 Toledo, so that along the ice the lake was 1 50 to 200 feet deep. 
 As the ice formed the eastern and northern shores, the lake 
 made no beach lines in Ontario. 
 
 Figure 6 shows diagrammatically the stages of Lake Mau- 
 mee and of the later lakes which occupied the Erie basin in 
 its step-like descent to its present level. From the highest to 
 the lowest is over 270 feet. 
 
 Lake Saginaw 
 
 During the final stages of Lake Maumee the ice in the 
 Saginaw Bay depression had retreated far enough so that a 
 small shallow crescent-shaped lake was formed along its 
 margin. This lake, known as Saginaw (Figure 5), became 
 larger when it received the overflow drainage from the Imlay 
 outlet river, and the waters of Lake Maumee and Lake Sagi- 
 naw flowed past the site of Maple Rapids into Grand River, 
 thence to Lake Chicago through a series of small lakes back 
 of the lake-border moraine near Paw Paw and Dowagiac, 
 Michigan. Lake Chicago also slowly expanded as the ice in 
 the Lake Michigan lobe melted northward. At first the chan- 
 nel of Grand River was narrow, but gradually, as the flow 
 from the lakes entered and scoured it, this became one of the 
 mightiest streams of the North American continent — a mile 
 to one and one-fourth miles wide and, near Grand Rapids, a 
 hundred and twent\' feet deep. 
 
 39
 
 40
 
 THE GLACIAL. LAKES 
 
 Lake Chicago 
 
 As Lake Maumcc increased In size Lake Chicago also in- 
 creased and was building its liigliest beach, the Glenwood, a 
 few miles south of Chicago. Lake Chicago never had tiie 
 varied history of the other lakes. Its several beaches are paral- 
 lel to the present beach and are so near Lake Michigan that 
 in places they actually have been undercut and destroyed by 
 the present lake. The outlet was through Des Plaines River 
 to the Illinois and the Mississippi — the "Chicago Outlet," now 
 utilized by the Chicago Ship and Drainage Canal. 
 
 Lake Arkona 
 
 The next important step in the development of the lakes 
 in the Erie basin was the rather sudden withdrawal of the ice 
 from the Thumb region of Michigan. All the lake waters to 
 the eastward fell to the level of Lake Saginaw, which had ex- 
 panded northeastward in a broad strait around the northern 
 end of the Thumb, and merged with it to form the larger lake 
 known as Arkona — the first lake to fill a part of the Lake 
 Huron basin. (Figure 7.) Lake Arkona endured for a long 
 time, as is shown by the height and strength of its beaches and 
 the size of the river deltas which were built into it and were 
 not wholly destroyed by powerful later events. That the lake 
 was large and deep and that the ice front stood far to the 
 north and east, is also shown by the strong gravelly beaches 
 which must have been made by waves that had a long 
 "fetch" on shore. The beaches show that Arkona, the largest 
 lake to occupy the Erie basin, was nearly three times as large 
 as Lake Erie. It extended northward as far as Gladwin, Michi- 
 gan, and eastward forty to fifty miles east of Buffalo, New 
 York, and received from the east the waters of the long nar- 
 row ice border drainage covering the Finger Lakes region. It 
 was the first lake to make definite beaches in Ontario, along 
 the southern edge of the Ontario nunatak around which 
 the ice had separated into two independent lobes — one in the 
 
 41
 
 ^ bS 
 
 42
 
 THE GLACIAL LAKES 
 
 Eric and the other in the Huron basin. As the ice retreated 
 Lake Arkona tell to lower levels, building beaches at each halt 
 in the lowering process, and the outlet continued through 
 Grand River to Lake Chicago. 
 
 Expanding Lake Chicago 
 
 As Lake Chicago continued to receive the discharge through 
 Grand River from Lake Saginaw and Lake Arkona, the lake 
 increased in size, particularly to the eastward, so that the 
 river entered it near Grand Rapids, rather than near the 
 Indiana line as at the earlier stage. During the retreat of the 
 Lake Michigan ice lobe the crescent-shaped lake had developed 
 several large bays along its eastern border, near the present 
 mouth of St. Joseph River, along the lower course of Kalama- 
 zoo River, and in the region west of Grand Rapids. The St. 
 Joseph, Kalamazoo, and Grand rivers abandoned their former 
 united course to the Kankakee, past South Bend, Indiana, and 
 each, in the order named, became an independent stream en- 
 tering a bay of Lake Chicago. 
 
 Restored Lake Saginaw; Lake Newberry 
 Then the ice made a powerful and rapid re-advance south- 
 ward. It cut off the waters in the Saginaw area and restored 
 Lake Saginaw to independence, but did not change its level 
 or its outlet to Grand River. It cut off the waters in the 
 Finger Lakes region of New York, to form independent Lake 
 Newberry, and caused them to find an outlet through Lake 
 Seneca and Susquehanna River. (Figure 8.) We know that 
 it was a re-advance of the ice which caused these changes, be- 
 cause the high Port Huron moraine — built when the glacier 
 halted — covers part of the Arkona beaches. As we trace the 
 Arkona beaches we find them suddenly disappearing under 
 the Port Huron moraine, south of Cass City, Michigan, but 
 they re-appear at the same level farther north in the Thumb 
 area and thus very evidently are buried under the mor.iine in 
 the intervening miles, 
 
 4)
 
 NE-SAW-JE-WON 
 
 Lake Whittlesey 
 
 Advance of the ice raised the level of the Arkona waters 
 about forty-four feet and ushered in a new lake which is 
 named Lake Whittlesey, for an early Ohio geologist. (Figure 
 8.) That Lake Whittlesey lasted for a long time is shown by 
 the fact that it had time to fill in the bays and to build one of 
 the strongest, straightest beaches in the lake region. The beach 
 was used as a highway by Indians, and later by white men, 
 from the time of the earliest Indian travel. In a direct line 
 like a railway embankment, it crosses the valleys of creeks 
 that formerly entered Lake Arkona, and in places it stands 
 twenty to twenty-five feet above the old valley floors to the 
 south. Such a strong beach must have been made by rapidly 
 rising water moved by powerful waves. The material for it 
 was torn from the earlier-built Arkona beaches, but when the 
 Whittlesey waters were so deep that bottom water was below 
 the level of wave action the Arkona beaches were protected 
 from wave cutting and thus preserved. Rivers flowing into 
 lakes Maumee and Arkona built deltas into the lakes, but 
 deltas and stream valleys were drowned by the rising Lake 
 Whittlesey. Thus, at first the shore had many wide estuaries 
 into the heads of which the rivers then built new deltas, as 
 streams are now filling the headwater levels of the drowned 
 bays and estuaries of the Atlantic coast from Maine to Vir- 
 ginia. But the new deltas above and back of the old did not 
 bulge into the lake beyond the beach, hence the peculiar con- 
 dition of deltas of Whittlesey time fitting into the beach like 
 insets in a mosaic. Gravel operators who procure gravel from 
 this old beach often find the gravel cut out by the fine 
 material of the inset deltas. However, near Alden, New York, 
 a small delta made by a stream flowing into Lake Whittlesey 
 buried the eastern end of the Arkona beaches ; and in Canada 
 glacial rivers developed such strength that they built deltas 
 along the northern shore. The location of the ice barrier 
 which retained this lake has been traced more precisely than 
 
 44
 
 T H t GLACIAL LAKES 
 
 that of any of the other glacial lakes, so that the position of 
 the ice front is known from Lake Michigan near Muskegon, 
 Michigan, to the Genesee valley in western New York. Parts 
 of the moraine which the ice built along its front were laid 
 in the deep water of lakes Saginaw and Whittlesey. These 
 sections were washed over and are not so pronounced a feature 
 of the landscape as the high morainic jumble of hills made 
 elsewhere by the ice in this, its most powerful advance and 
 longest stand in the area of the Great Lakes. 
 
 Although the advancing ice closed the broad strait tiiat had 
 made Lake Saginaw a part of Lake Arkona, and separated these 
 lakes, an outlet for Lake Whittlesey was developed past the 
 site of Ubly in Huron County, Michigan, which carried the 
 waters of Lake Whittlesey into the lower Lake Saginaw and 
 thence to Grand River, Lake Chicago and the Mississippi. 
 
 Lake Wayne 
 
 Again the ice retreated, and in the climax of this retreat 
 the waters fell abruptly eighty to eighty-five feet and col- 
 lected in a lake known as Wayne, causing the reunion of Lake 
 Saginaw with the larger lake to the east. The boundaries of 
 Lake Wayne have not been continuously traced, but it is so 
 named because of the strength of the beaches at this elevation 
 near W^ayne, Michigan. Inasmuch as an outlet lower than the 
 Grand River outlet has been found near Syracuse, New York, 
 it is probable that for the first time the glacial lakes had an 
 eastern outlet to the Hudson River valley. This outlet shows 
 that the waters fell over cliffs in the hills south of Syracuse, 
 making falls as high as Niagara. It is also possible that the 
 outlet may have been to the north, past the ice front to the 
 region of Little Traverse Bay in Michigan, and thence to 
 Lake Chicago; but evidence supporting this theory is not as 
 conclusive as that for an eastern outlet. Also, Lake Saginaw 
 may have had a northern outlet and Lake Wayne an eastern 
 outlet. (This is just one of tlie many interesting perplexities 
 
 4J
 
 NE-SAW-JE-WON 
 
 in the lake history.) It is apparent that a lake corresponding 
 to Lake Arkona may have existed again for a short time when 
 the Whittlesey waters reached the former Arkona level on 
 the way down to the level of Lake Wayne. 
 
 Early Lakes of the Superior Basin 
 
 About this time the ice lobe in the Superior basin had re- 
 treated north of the drainage divide, and five small lakes had 
 formed along its borders. The largest of these, glacial Lake St. 
 Louis (formerly called Lake Upham), was held between the 
 Superior ice lobe on the east and the Keewatin ice on the west 
 and covered the central drainage basin of St. Louis River, 
 south of the Mesabi Range in Minnesota. Its outlet was down 
 St. Louis River to the ice border, thence along the border to 
 Kettle River, a tributary of St. Croix River. A second small 
 lake formed in southeastern Carlton County, Minnesota, in 
 the extreme western end of the Lake Superior basin. It has 
 been named Lake Nemadji, as Nemadji River flows across its 
 bed. Its outlet was westward to Moose Lake and Kettle River 
 and to the St. Croix. In northern Douglas and Bayfield 
 counties, Wisconsin, glacial Lake Brule covered about twenty 
 square miles of the drainage valley of Bois Brule River. Its 
 outlet was southward through St. Croix River to the Mis- 
 sissippi. At first it received drainage along the ice border 
 from as far east as Baraga County, Michigan, but later the 
 border drainage expanded into two other lakes, Ashland and 
 Ontonagon. Lake Ashland covered several townships in 
 northeastern Ashland County, Wisconsin, and extended to 
 the eastern slope of Bayfield Peninsula. It was separated from 
 Lake Brule by the highlands of the Copper Range but had an 
 outlet across Bayfield Peninsula into Lake Brule. Farther 
 east, glacial Lake Ontonagon occupied much of the drainage 
 basin of Ontonagon River, south of the Copper Range in the 
 Northern Peninsula of Michigan. Its outlet was the peculiar 
 narrow channel, one-eighth to one-fourth of a mile wide and 
 
 46
 
 1111. GLACIAL LAKES 
 
 twenty to forty feet deep, leading from the present Lake 
 Gogebic to Presque Isle River, thence in a northward loop 
 almost to Lake Superior, thence westward again past Bes- 
 semer, Michigan, and Saxon, Wisconsin, into glacial Lake 
 Ashland in the norihwcsiern corner of Iron County, Wiscon- 
 sin, The ice border drainage from Baraga County eastward 
 drained southward into glacial Lake Chicago. The old beds of 
 glacial lakes Brule, Ashland and Ontonagon are the fertile 
 agricultural lands in an otherwise rocky infertile region. 
 
 Lakl Warrln' 
 At length came another oscillation of the ice, and the east- 
 ern outlet for the lakes in the Huron-Erie basin was closed. 
 The lake waters again were raised above the level of Lake 
 Wayne and created the lake known as glacial Lake \\'\irren. 
 (Figure 9.) It was at the level of Lake Saginaw and once 
 more deprived that lake of its independence. But despite the 
 southward oscillation of the ice front which closed the east- 
 ern outlet, the ice had melted far enough north so that now 
 the lakes entered the Ontario basin. The outlet returned to 
 Grand River, and the waters from all the lakes, including the 
 waters of the Finger Lakes region of New York and of Lake 
 Simcoe in Ontario, drained to the enlarged Lake Chicago and 
 thence to the Des Plaines-Illinois, or Chicago, outlet to the 
 Mississippi. Lake Warren repeated the history of Lake Whit- 
 tlesey : it was the result of an ice advance, its waters were raised 
 above the level of its immediate predecessor lake, and its 
 violent storm waves tore into the material of the Lake Wayne 
 beaches to build its own strong, sandy and gravelly beaches, 
 which also have been used by men for travel routes. 
 
 Laki: Dulu ih 
 
 In the Superior basin the ice retreated step by step until the 
 
 western end of the basin was uncovered. Lakes St. Louis and 
 
 Nemadji drained into Lake Brule, and all became a part of 
 
 Lake Duluth — the ancestral Lake Superior. This was a cres- 
 
 47
 
 ^^^ 
 
 V 
 
 48
 
 THK GLACIAL LAKES 
 
 cent-shaped lake around the end of the Superior lohe, which 
 drained throui;h the old Lake Brule outlet to St. Croix River 
 and the Mississippi. Lake Ontonagon was lowered about 200 
 feet, and its bed became land, but narrow bays of Lake Duluth 
 extended a few miles up each of the tributaries of Ontonagon 
 River south of the Copper Range. 
 
 Lake Elkton 
 
 Powerful as were Lakes Warren, Chicago and Duluth, they 
 also gave way to lower lakes, as the ice once again retreated 
 and drew the lake waters down. Lowering was slow and halt- 
 ing, and at each halt the lake had time to make a beach. At 
 two such halts prominent beaches, the Grassmere and Elkton, 
 were built. During that period the waters of the Huron and 
 Erie basins were connected by a broad shallow strait across 
 the site of the St. Clair and Detroit rivers and Lake St. Clair. 
 As the lake level fell parts of the strait became so narrow that 
 the waters flowed through it with a river-like current across 
 the submerged Port Huron moraine, eleven miles south of 
 Port Huron, Michigan. This stream may be considered the 
 ancestral St. Clair River. Through it the waters of Lake 
 Saginaw were brought to the level of the next lake in the 
 Erie basin — glacial Lake Elkton (formerly named Lake 
 Lundy.)"" (Figure 10.) 
 
 When the lakes settled to the Elkton level the Grand River 
 outlet was abandoned, because a lower outlet was uncovered 
 eastward through the Marcellus-Cedarvale channel which 
 crosses the hills southwest of Syracuse, New York. This out- 
 let passed over the Niagaran escarpment and was shifted west- 
 ward over it from place to place as the water level lowered. 
 The outlet stream falling over the escarpment made falls as 
 high and imposing as Niagara, and although little or no water 
 now descends (ner these "fossil" cataracts, they add to the 
 
 •Dr. Frank Lcvcrctt chnriKcd the name of this lake fr<ini l.undy tn I'lkton in 19^9. 
 
 49
 
 50
 
 THE GLACIAL LAKES 
 
 grandeur of the scenic beauty in western New York, particu- 
 larly near Jonesville and in the Blue I lills. 
 
 At the close of Lake Elkton time the ice had retreated 
 northward tar t'ni)ui;h so tii.u the Cjrcat Lakes began to shrink 
 into the Hniiis ot the ancient river basins and to assume some- 
 what their present appearance. In the Superior basin Lake 
 Duluth extended eastward to the highlands of Keweenaw 
 Peninsuhi and the Huron Mountains, and westward and 
 northward beyond Dulutii, Minnesota, and lort W'ilham 
 Ontario, but its outlet was still through the Bois Brule-St. 
 Croix River to the Mississippi. 
 
 Lake Chicago had enlarged northward until it occupied 
 Green and Traverse bays. It received considerable drainage 
 from the ice fronts in the Northern and Southern peninsulas 
 of Michigan and continued to drain to the Mississippi. Lake 
 Saginaw had merged with Lake Likton; a large lake in the 
 Simcoe basin of Ontario was connected with Lake Elkton by 
 a stream flowing along the ice front; the western end of the 
 Ontario basin was occupied by the eastern part of Lake Elk- 
 ton, extending in long narrow bays around the Ontario ice 
 lobe. Overflow discharged eastward over high cataracts and 
 drained along the ice border past Syracuse and down the 
 Mohawk valley to the Hudson. This drainage channel is 
 known as the Syracuse outlet. 
 
 The effect of lowering the outlet through the Syracuse 
 channel \vas to increase the power of the currents flowing 
 over the old submerged moraines which marked the former 
 positions of the ice front south of Port Huron and which 
 had acted as barriers holding up the waters in the Saginaw and 
 Huron basins. These moraines are south of Port Huron, at 
 Detroit, and near Trenton — soutliwest of Detroit. The 
 morainic material was easily cut tiirough by several streams, 
 
 51 
 
 UBRARY 
 
 UNFVERsmr OF iiumxs 
 
 Kf URBANA -CHAMPAIGN
 
 52
 
 THE BIRTH OF NIAGARA FALLS 
 
 as for a time two St. Clair rivers flowed in parallel courses, and 
 Detroit River resembled a wide loosened braid of many 
 strands. But in time the currents chose the eastern channels 
 and took almost their present courses. When these rivers 
 developed, the lakes in the Huron and Hrie basins were finally 
 separated, and a fairly stable condition was established. This 
 initiated perhaps the most interesting episode in the long lake 
 history — the beginning of glacial Lake Algonquin, the largest 
 of the glacial lakes and the last to be controlled by the ice 
 sheet. Up to this time the important lakes were in the Erie 
 and connecting basins; from now on the northern lakes be- 
 come important. 
 
 Early Lake Algonquin; Lake Tonawanda 
 
 The early Lake Algonquin (Figure 11) occupied only the 
 southern part of the Huron basin. The outlet at Port Huron 
 discharged its waters southward into Lake Erie, thence along 
 the ice front in the Ontario basin, past Syracuse and down the 
 Mohawk valley to the Hudson. Correlative with it were 
 lakes Chicago and Duluth in the west and Lake Tonawanda 
 in New York. When the ice front withdrew back of the 
 Niagaran escarpment and the waters in the Ontario basin be- 
 gan to lower, a broad shallow lake was left for some time, 
 stretching for fifty miles east of Buffalo, New York, and eight 
 or ten miles west of the present location of Niagara Falls. 
 Tonawanda Creek now flows on the bed of this short-lived 
 lake which wc know as glacial Lake Tonawanda. 
 
 The waters of Lake Duluth reached Lake Chicago by flow- 
 ing southward from near Marquette, Michigan, through the 
 rocky channel now used by the short northward-flowing Au 
 Train River and the longer southward-flowing Whitefish 
 River, having abandoned the higher western outlet to St. 
 Croix River. Lake Chicago still used the Chicago outlet, via 
 the Des Plaines-Illinois-Mississippi rivers. The ice later with- 
 drew from the high lands west of Alpena, Michigan, and 
 
 J}
 
 GLACSAL LAKE IROQUOffS 
 
 Dufferiri Ids. 
 
 FIGURE 12.— DIAGRAM OF NIAGARA RIVER GORGE 
 
 SHOWING RELATIONSHIPS TO THE LAKES. 
 
 Modified frovi Gilbert — U. S. Geological Siirvey, Niagara Folio. 
 
 54
 
 CUTTING NIAGARAS GORGE 
 
 ended the independence of Lake Chicago, uniting; it across 
 northern Miclii^an witli the early Lake Algonquin. Llowever, 
 as the two lakes were at the same level, it is probable that for 
 a time both the Chicago and the Syracuse outlets were used. 
 
 Niagara River and i hi Birth of the Falls; Beginning 
 oi Independent Lake Erie 
 
 At this period in the Lake drama Niagara River comes on 
 the stage to play an important part. When the ice of the 
 Ontario lobe withdrew far enough north so that the melt 
 waters fell below the level of the Niagaran escarpment, the 
 overflow from lakes Erie and Tonawanda fell over the rocky 
 ledge near Lewiston, New York; then Niagara Falls was born, 
 and Lake Erie became independent. No longer fed by glacial 
 streams, Erie waters became warm and gradually became 
 populated with fresh-water fish. At first the water descended 
 in a great cascade, but in a short time a pool. Cataract Basin 
 (Figure 12), was scoured at the base of the cascade, and un- 
 dercutting of the limestone ledge followed. Four other spill- 
 ways northward from Lake Tonawanda were in use, but the 
 spillway at Lewiston was the largest, and as it also received 
 the overflow from Lake Erie it could cut faster. In time it 
 drained Lake Tonawanda westward and caused the abandon- 
 ment of the spillways at Holly, Medina, Gasport and Lock- 
 port, New York, leaving them as short gorges in the escarp- 
 ment carrying small streams with cascades. Lake Tonawanda 
 was drained, until now all that is left of it is the broad part 
 of Niagara River above Goat Island. 
 
 During the life of early Lake Algonquin, about 2,000 
 feet of the Niagara gorge was cut back from the escarpment. 
 This section is known as the Lewiston Branch Gorge. Or- 
 dinarily a stream flowing from a lake has no cutting tools 
 with which to deepen its channel, for rock debris carried into 
 the lake is left on the bottom, and the outlet stream flows 
 clear. Niagara River has always carried clear water, but it 
 
 55
 
 56
 
 THE GLACIAL. LAKES AND LAKE li R 1 1 
 
 flows northward over a i^ently southward -sloping bed of 
 thick hmcstonc. When tlie water of the river lalls over the 
 escarpment it drops with such force that it breaks up the 
 rocks below and thus gives the stream below the falls powerful 
 cutting tools. Under the limestone are thick beds of soft 
 shales — the same shales in which Green and Georgian bays 
 are carved. Below the shales is a thin hard limestone which 
 furnishes heavy tools when its fragments fall into the river; 
 under this is another layer of soft shales, and then a resistant 
 sandstone about at the water level below the falls. The water 
 dashing against the rocks at the base of the falls hurls the 
 fragments upward against the soft shales, smashing, biting, 
 breaking into them, and so undermining the sandstones and 
 limestones. The thick heavy upper limestone is thus under- 
 cut until it resembles an overhanging cornice; it becomes top- 
 heavy and then huge masses of it break loose and fall into the 
 maelstrom below, adding to the tools already there. This 
 process of undercutting the shales and breaking off the un- 
 supported limestone cornice has been going on ever since the 
 first water dashed against the shales in the escarpment cliff at 
 Lewiston, eighteen to twenty thousand years ago, and has been 
 the most important factor in cutting the Niagara gorge. The 
 gorge has been deepened by the river with rock-fragment 
 tools supplied from the fallen sandstone and limestone blocks, 
 but the varying widths and other characteristics of the gorge 
 are a part of the story of the lakes. 
 
 The Second Stage of Lake Algonquin; Lake Iroquois; 
 
 Lake Erie 
 
 The early stage of Lake Algonquin passed when the ice 
 retreated far enough to open an outlet lower than the out- 
 lets at Port Huron and Chicago. When the level of the lakes 
 became stationary at the level of this new outlet the second 
 stage of Lake Algonquin was established, and it endured for 
 a long time. (Figure 13.) As early Lake Algonquin was 
 
 S7
 
 NE-SAW-JE-WON 
 
 passing into the second stage, the ice in the Ontario basin had 
 melted so far to the northeast that the long narrow body of 
 water between the ice and the Niagaran escarpment increased 
 to a lake overflowing the basin. This body of water has been 
 named Lake Iroquois and is the ancestor of Lake Ontario. Re- 
 treating from the vicinity of Syracuse, the ice uncovered a still 
 lower outlet near Rome, New York, through which the waters 
 of Lake Iroquois spilled down the Mohawk valley to the Hud- 
 son and deepened the channel which centuries later was to 
 serve as a part of the Erie Canal. Lake Iroquois was fed not 
 only by the waters of the melting Ontario ice lobe but also by 
 the overflow from the vast second Lake Algonquin, which dis- 
 charged through a lower outlet than the Port Huron-Lake 
 Erie-Niagara River route. All the waters of the upper lake 
 basins — Superior, Michigan, Huron, Saginaw and Georgian 
 Bay — were connected in a broad expanse of lake. Its shores 
 extended well beyond the borders of the present waters oc- 
 cupying those basins, and it covered the eastern part of the 
 Northern Peninsula of Michigan, except for a few small 
 islands. The entire overflow passed eastward through the low 
 col in the vicinity of Kirkfield, Ontario, down Trent River 
 to the Ontario-Lake Iroquois basin — a channel known as the 
 Kirkfield-Trent River outlet. Thus, when Lake Algonquin 
 fell to the level of the Kirkfield outlet its waters reached the 
 Atlantic Ocean at New York through Lake Iroquois, Mohawk 
 River and the Hudson valley. The Hudson valley was then a 
 marine estuary, drowned when it was flooded by the rising 
 Atlantic Ocean. Lake Erie was a small independent lake in the 
 eastern part of the Erie basin, no longer fed by the waters of 
 melting ice, and was somewhat below the level of the lake 
 today. It had as tributary a stream which flowed from the 
 swampy region which is now Lake St. Clair, through the 
 channel (perhaps a swampy slough) of Detroit River, and 
 across the western floor of the old lake. During this period 
 Niagara River, receiving only the overflow from this small
 
 CKUSTAL MO\ LMLNTS Ol THL LARTH 
 
 Lake Erie, could cut but a narrow gorge — the part beginning 
 about 2,000 feet above the mouth of the gorge and extending 
 to the bend just norili of Niagara University, a distance of 
 about one and one-eighth miles — known as the Old Narrow 
 Gorge. 
 
 Crustal Movements of the Earth 
 
 Up to this time the story of the lakes has been a tale of the 
 carving of valleys by pre-glacial rivers, of the coming of the 
 ice and the consequent deepening and widening of these val- 
 leys, of melting ice and filling of the basins with glacial waters. 
 Now another force, which all the time had been gently active, 
 becomes most important in the story. 
 
 The rock crust of the earth rests upon a more-or-less plas- 
 tic, yielding interior. Thus, it is probable that so great a mass 
 of ice covering the northern half of the continent and weigh- 
 ing millions of tons must have burdened the land surface and 
 depressed it far below the level it had attained in the highlands 
 where the glaciers first developed; also, it is plausible that as 
 the ice melted the land would gradually rise again when re- 
 lieved of this weight. From the evidence that the lakes have 
 left us, this seems to be exactly what happened. 
 
 As lake surfaces are level, the beaches and strand lines must 
 be essentially horizontal when made. However, studies of the 
 glacial lake beaches show that, although their southern parts 
 are horizontal, as we follow them northward they gradually 
 rise in elevation. Only an uplift of the continent after the 
 beaches had been made could so disturb their horizontality. 
 The Whittlesey and Warren beaches are tilted upward toward 
 the north, showing that the depressed portion of the continent 
 started to be re-elevated when the ice had retreated half-way 
 across the lake region. It is notable that the places of initial 
 tilt of the beaches of each of the lakes, which are well defined 
 and readily observed on opposite sides of the lakes, lie on prac- 
 tically straight connecting linos. These arc known as hinge 
 
 J9
 
 60
 
 M O R L WORK Oh NIAGARA RIVER 
 
 lines, north of which the beaches arc upcanted somewhat 
 as a partly-opened trap door. The hinge Hne north of wliich 
 the continent first uphfted extends from Aslitabula, Oliio, 
 northwestward across Lake St. Clair, and bends to Lake Michi- 
 gan west of Grand Rapids. South of that line the Lake 
 Whittlesey beaches are horizontal; north of it they are up- 
 tilted. That the uplift was somewhat spasmodic is shown 
 by the fact that the Lake Warren beaches are uptilted north 
 of another hinge line about fifteen miles north of and parallel 
 to the Whittlesey hinge. 
 
 By these deformed beaches we know that the forces of 
 continental uplift were active even before the time of Lake 
 Algonquin, but they had played no very important part as 
 yet in the development of the lakes. By the time the Kirk- 
 field outlet of Lake Algonquin was well established, and a river 
 wider than the St. Clair had scoured a broad channel down 
 the Trent River valley, and the lake had made well-defined 
 beaches and other shore formations, the continent began to 
 rise more rapidly; then the waters of the lakes were spilled 
 southward out of their basins and again found their old out- 
 lets past Port Huron and Chicago; and for a time Lake 
 Algonquin had three outlets: to Lake Iroquois, to Lake Erie, 
 and to Mississippi River through the old Chicago outlet. 
 (Figure 14.) Spilling the waters on the south shores destroyed 
 the beaches of the Kirkheld stage in Michigan, but they are 
 preserved around Duluth and in the Ontario areas. The down- 
 cutting, and therefore lowering, of the outlet past Port Huron 
 diverted the overflow from the Chicago outlet, so that in the 
 latter part of this stage Lake Algonquin was drained through 
 lakes St. Clair, Rouge and Erie. Lakes St. Clair and Rouge 
 were small transitional lakes in depressions of the former 
 strait connecting the Huron and Erie basins during Lake 
 Elkton time, and now held the Algonquin overflow. They 
 were large enough and lived long enough to make faint but 
 well-defined beaches. The uplift raised the level of the Rome, 
 
 61
 
 NE-SAW-JE-WON 
 
 New York, outlet of Lake Iroquois and caused the water to 
 be ponded back on the southern shores, but it was not high 
 enough to cause a reversal of flow back into Lake Erie. At 
 this stage Lake Iroquois made its strongest beach. 
 
 More Work of Niagara River 
 
 The early increase in volume in the rejuvenated Lake Erie 
 increased the activity of Niagara River: a greater volume of 
 water flowed over the falls, and a wider gorge was cut — that 
 part of the gorge extending from the bend north of Niagara 
 University up-stream as far as the head of Foster Rapids. 
 When the Chicago outlet was abandoned and all the water 
 of the upper lakes poured over Niagara, the wide gorge from 
 the head of Foster Rapids to the upper edge of the Eddy 
 Basin above the Whirlpool was made. Together these parts 
 of the gorge are known as the Lower Great Gorge. (Figure 
 12.) Curiously, the Whirlpool is not a part of the gorge 
 proper. Its story is actually older than that of the gorge in 
 which it now lies. At some time before the last ice invasion, 
 a river flowing from southeast to northwest had plunged over 
 the Niagaran escarpment at the site of the little Canadian 
 town of St. David. Like the Niagara, this river, which has 
 been named St. David, cut a gorge back from the escarpment 
 as far as the Eddy Basin just above the Whirlpool. The on- 
 coming glacier destroyed the river and filled its gorge with 
 rock debris (drift) , which then became considerably cement- 
 ed together although not as solid as rock. Later, when the 
 Niagara had cut back to the old buried gorge, the northeast 
 wall of the gorge supporting the falls became thin and 
 crumbled, giving the waters access to the less-resistant ma- 
 terial filling the old channel. The waters of Niagara, plunging 
 with great force and volume, soon scoured away the glacial 
 debris, swirled and hurled its heavy tools northwest into the 
 buried gorge until it had made the Whirlpool. The depth of 
 the Whirlpool is due in part to the depth of the buried gorge 
 
 61
 
 THE RECORDS OF ALGONQUIN TIME 
 
 which the Nlaj^ara resurrected. The Lower Reef, at tlie out- 
 let of tlie pool, is the remnant of the breached wall of tiie old 
 gorge; the Upper Reef marks the site of the ancient St. 
 David's Falls. At present tlu- current, dashing along the right 
 side of the gorge, swirls around to the left in the pit of the 
 Whirlpool, swings back upstream into the Lddy Basin and 
 then downstream over the Lower Reef, cutting deeper and 
 deeper into the soft shale bed of the pool and also cutting 
 against the drift fill of the ancient St. David's Gorge. A small 
 stream, Bowman Creek, enters the \\'hirlpcK)l from the old 
 gorge and carries its contribution of rock waste as cutting 
 tools for the Niagara. This section of the gorge, made during 
 the two-outlet stage of Lake Algonquin, is two miles long, 
 showing the long time that the second stage of this lake 
 existed. 
 
 The Records of Algonquin Time 
 
 The rising deepening waters of Lake Algonquin, whose 
 powerful waves beat with force against the shores, built 
 strong beaches which are marked by well-defined cliffs and 
 beach ridges in the landscape about the present three upper 
 lakes — Michigan, Superior and Fiuron. As one drives toward 
 the shores of these lakes, the highway leads from rolling mo- 
 rainic uplands, down over cliff to terrace, and across the sev- 
 eral beaches of Lake Algonquin. In places later lakes have cut 
 away the Algonquin beaches, but in the main these beaches are 
 the high cliffs set some distance back from the present lake 
 shores. Tracing of the beaches shows that the Chicago outlet 
 is choked by the Algonquin beach; that the tip of the 
 Southern Peninsula of Michigan, north of Indian River and 
 Petoskey, was an archipelago; and that only the highest points 
 of Keweenaw Peninsula were above water as islands. \ he 
 great inland lakes of Michigan — Torchlight, Charlevoix, Wal- 
 loon, Mullet, Douglas, Burt and others — with their high- 
 cliffcd terraces, are remnants of lake Algonquin. The "in- 
 
 63
 
 NE-SAW-JE-WON 
 
 photo by Michigan Department of Conservation 
 
 PLATE 4.— ARCH ROCK, MACKINAC ISLAND 
 
 A SEA ARCH CUT IN LIMESTONE OF THE ALGONQUIN SHORE. THE 
 NIPISSING BEACH BELOW HAS BEEN DESTROYED BY MODERN WAVE ACTION. 
 
 land route" of lakes and low portages between Cheboygan 
 and Petoskey is a channel of the Algonquin archipelago. The 
 interesting cliffed scenic beauty of Mackinac Island was pro- 
 duced by the work of the ancient lakes. During Algonquin 
 time Mackinac Island was triangular in shape and only about 
 three-fourths of a mile long, rising eighty feet above the lake 
 level. On its shores the beating waves of Lake Algonquin 
 carved Sugar Loaf and Arch Rock. From this small ancient 
 island Mackinac slopes by cliff and terrace to the present 
 lake level. Each terrace and its backing cliff represents a level 
 of the ancient lakes as well as a step in the slow uplift of the 
 continent. In places the waters of later lakes have cut into 
 
 64
 
 THl Rl C ORDS c)l ALGONQUIN T I M Iv 
 
 photo by Michigan Depdrtmcnl of CoHtervtliom 
 
 PLATE J.— SUGAR LOAF ROCK, MACKINAC ISLAND 
 
 A LIMESTONE REMNANT OI THE ANCIENT ALGONQUIN SHORE, NOW FAR 
 INLAND AND ABOVE LAKE LEVEL. 
 
 the beaches, so that the chffs now rise sheer from the Huron 
 to the old Algonquin shore, but the general view of the island 
 is of land rising by great steps from Lake Huron. 
 
 Interesting and arresting are these raised beaches, with 
 their arched rocks, wave-cut cliffs, sea caves and grottos, and 
 shingle beaches high above lake level; they tell a story not only 
 of rising and falling water but of a rising land. If we sail 
 along the lakes we see the interesting rocks, like little ships, 
 cut from the mainland and jutting into the lake at the tip of 
 the Thumb of Michigan — at Pointe Aux Barques. They are 
 cut in the rocky shore cliff of Lake Algonquin, which at the 
 Pointe is only ten feet above the level of Lake Huron; but 
 when we reach Mackinac we find the same shore — which we 
 
 65
 
 NE-SAW-JE-WON 
 
 m 
 
 photo by Michigan Deportment of Conservation 
 
 PLATE 6.— POINTE AUX BARQUES, SEA CAVES AND ARCHES 
 
 CUT IN THE MARSHALL (MISSISSIPPI AN ) SANDSTONE OF THE ALGONQUIN 
 shore; HURON COUNTY, THUMB OF MICHIGAN. 
 
 could have followed all the way on the mainland — to be 194 
 feet higher. The elevation of this beach at Port Huron is 
 607 feet above sea level, at Mackinac 801 feet, near Munising 
 in the Northern Peninsula 948 feet — 341 feet higher than at 
 Port Huron; and on Keweenaw Peninsula west of Calumet 
 it is at 1,080 feet, rising to 1,100 feet near Mohawk and to 
 1,110 feet near CHff. If we follow the beach eastward from 
 Port Huron to the Kirkfield outlet, we find ourselves gradu- 
 ally mounting higher, until at Kirkfield, Ontario, the beach 
 is 883 feet above sea level — 276 feet above its Port Huron 
 elevation. North of Georgian Bay evidence of the beaches 
 shows that the country has been lifted 600 to 700 feet. The 
 Algonquin beaches near Grand Bend, Ontario, on the eastern 
 
 66
 
 THE LAST Ol THIL GLACIAL LAKES 
 
 shore of Lake Huron, at Riclimondville on the western shore, 
 at Standisli near Sai;inaw Bay, and near Manistee on the east- 
 ern Lake Michigan shore, are at the same elevation, thus 
 estabhshing the position of the Algonquin hinge line north of 
 which the land has uptilted. At times uplift was slow and 
 steady so that the beaches were actually split while forming, 
 and several beaches of the lowering lake actually come to- 
 gether at a common point — just to add to the complexities. 
 
 The records made along the eastern boundary of the glacier 
 during Lake Algonquin time have not been fully worked out; 
 but when the ice sheet in the St. Lawrence valley had re- 
 treated to the northern edge of the Adirondack Mountains, 
 a new outlet for Lake Iroquois somewhat lower than that at 
 Rome, New York, was found, and a channel was scoured 
 along the northern mountain slope toward Lake Champlain. 
 Continental uplift shortened the life of this stage, which is 
 known as Lake Frontenac. 
 
 When the ice barrier withdrew farther north the land was 
 so low that the sea, which had gradually risen with the return 
 to it of vast quantities of glacial waters, entered the valley of 
 the St. Lawrence (as earlier it had entered the valley of the 
 Hudson), filling the Ontario basin with ocean water, 
 as is shown by the remains of marine or salt-water animals left 
 in the deposits. This marine embayment has been named 
 Gilbert Gulf. 
 
 As it must come to everything, an end came to Lake Al- 
 gonquin. The barrier holding it to the highest level finally 
 gave way when the ice retreated north of North Bay, On- 
 tario, and opened an outlet even lower than the Kirkfield 
 outlet. Then through a short river bordering the ice front the 
 waters of the upper lakes poured into the marine gulf which 
 had flooded the valleys of the St. Lawrence and Ottawa rivers, 
 of Lake Champlain and Hudson River. This great marine 
 estuary is known as the Champlain Sea. Evidence is lacking to 
 determine the time duration of this, the Ottawa, stage of the 
 
 67
 
 68
 
 THE N 1 IM S S 1 N C. C, R 1 A 1 I. A K l- S 
 
 lake, but it marks the end of Ali;onquin, the last of the glacial 
 lakes (Iii;ure 15), and was a transition to a new lake, tor the 
 waters tell to a lower level when the ice had completely with- 
 drawn from the basin of the Cireat I akes. 
 
 Thi: Nipissing Great Lakes 
 
 When the ice was no longer a barrier the lakes were drawn 
 down almost to their present levels in the five separate basins. 
 The three upper lakes which occupied the Superior, Michigan, 
 and Huron-Georgian Bay basins are known as the Nipissing 
 Great Lakes. (Figure 16.) The beaches are strongest near 
 the present Lake Nipissing, in Ontario near the North Bay 
 outlet, hence the name. The col at North Bay was the low- 
 est along the Nipissing shore, so the outlet was developed 
 through it down the Mattawa River into the Ottawa — from 
 which the sea had withdrawn. By the time the Mattawa- 
 Ottawa River outlet was well established the land had risen 
 so that the sea retreated eastward to the limits of a narrow 
 estuary reaching up the St. Lawrence and Ottawa valleys to 
 a short distance west of Ottawa. The Champlain-Hudson 
 valley remained filled with marine waters. The old North 
 Bay outlet at the present time is marked by lakes and swamps, 
 with ct)nnecting dry valleys which show the marks of scour 
 of a great river. It is the route by which Marquette, Allouez, 
 Mesnard and other early Jesuit missionary explorers reached 
 Georgian Bay and Lake Superior. 
 
 In the early stages the Nipissing lakes built beaches which 
 have been nearh' obliterated except in a small area near the 
 northeast corner of Lake Superior. The strong beach we 
 know as the Nipissing beach was made when the lake was 
 rising, its waters being spilled on its southern shores as the 
 continent continued to uptilt to the north. That the tilting 
 was rather rapid is shown b\ the "greedine«>s" with which this 
 lake bit into the old Algonquin beaches where they had been 
 cut as cliffs. In the area where the beaches are horizontal the 
 
 69
 
 70
 
 THE NIPISSING GREAT LAKES 
 
 ?holo by Michigan Deptrlment of Conieritliom 
 
 PLATE 7.— CASTLE ROCK, ST. IGNACE, MICHIGAN 
 
 A REMNANT OF THE NIPISSING SHORE. 
 
 Nipissing beach is ten to twelve feet below the Algonquin, 
 but northward from the hinge line — extending from Great 
 Bend, Ontario, to Manistee, Michigan — they become widely 
 separated, until at Mackinac Island they are more than 175 
 feet apart, and over 360 feet separates them at Sault Ste. Marie. 
 In the Huron and Michigan basins the Nipissing beaches have 
 been lifted from the horizontal position along the same hinge 
 line as the Algonquin, but in the Superior basin they seem to 
 have a hinge of their own. Like the Algonquin beaches, the 
 Nipissing have also been destroyed in many places by the 
 work of the modern lakes — notably along the east side of the 
 Thumb north of Port Huron, along the east coast of Lake 
 Huron, and on both sides of Lake Michigan. Elsewhere they 
 are very pronounced, paralleling the present shore at no great 
 
 71
 
 NE-SAW-JE-WON 
 
 Photo by Michigan Department of Conservation 
 
 PLATE 8.— THE "FORTRESS" OF THE PICTURED ROCKS 
 
 NEAR MUNISING, MICHIGAN, ON LAKE SUPERIOR; NIPISSING AND MODERN 
 
 KM. i lilliMBft. i * !' - »i M« i j m i ' i< m iii l i «»' » ' i 
 
 Photo by Michigan Department of Conservation 
 
 PLATE 9.— CLIFF AND SEA CAVE 
 
 IN CAMBRIAN SANDSTONE, LAKE SUPERIOR; NIPISSING AND MODERN 
 
 72
 
 THE NIPISSING GREAT LAKES 
 
 photo by Michigan Drparlmrnl of Conirridtion 
 
 PLATE 10.— STACKS AND SEA CAVES 
 
 STACKS ON NIIMSSING SHORES; CAVES ON MODERN SHORES OF LAKE 
 SUPERIOR; CLIFFS OF CAMBRIAN LAKE SUPERIOR SANDSTONE. 
 
 distance back of it, and in some places — as on the rampart- 
 bastioned shore east of Marquette — being directly above the 
 present shore. Nipissing beaches are somewhat more sandy 
 than the Algonquin and in places — as at Grand Marais on the 
 Superior shore — are buried under great dunes. 
 
 Where rock clitfs formed tiie shore tiie powerful Nipissing 
 waves carved caves and grottos, cut pinnacles — called stacks — 
 from the mainland, and carved deep bays or fjords in the 
 islands — particularly in Isle Royale which became an island 
 when the waters of the lakes were drawn down to the Nipis- 
 sing level. Pulpit Rock and Scotts Cave, of Mackinac Island, 
 and the isolated pinnacles of rock near St. Tgnace, are relics oi 
 the Nipissing shore. Sea caves and stacks around Lake Supe- 
 
 73
 
 NE-SAW-JE-WON 
 
 photo by Michigan Department of Comeriation 
 
 PLATE 11.— CHAPEL ROCK 
 
 NIPISSING AND MODERN SHORES OF LAKE SUPERIOR; CAMBRIAN LAKE 
 SUPERIOR SANDSTONE. 
 
 Photo by Michigan Department of Conservation 
 
 PLATE 12.— WAVE-CUT CLIFFS 
 
 NEPISSING AND MODERN SHORES OF LAKE SUPERIOR; CAMBRIAN LAKE 
 SUPERIOR SANDSTONE. 
 
 74
 
 THE NIPISSING GREAT LAKES 
 
 Photo by Michigan Dcpdrtment of CoHurviliou 
 
 PLATE 13.— MINER'S CASTLE 
 
 REMNANT OF NIPISSING SHORE OF LAKE SUPERIOR; CAMBRIAN LAKE 
 SUPERIOR SANDSTONE. 
 
 rior, the carvings in the upper levels of the Lake Superior sand- 
 stone facing Lake Superior from the Pictured Rocks east- 
 ward, the muraled cliffs of Grand Island, the skerries of Isle 
 Royale, Monument Rock, towering seventy feet above the 
 plain between Tobin Harbour and Duncan Bay on Isle Royale 
 — all these shore formations now high and dry were cut by 
 the powerful waves of Lake Nipissing. But at the western 
 end of Lake Superior the Nipissing beach seems to pass under 
 the present beach; and that belongs to the story of the pres- 
 ent Great Lakes and of the deformation of their shores by the 
 tilting of the continent. The movement which withdrew 
 the lakes from their eastern shores and spilled the waters over 
 the southern shores, in one area lifted the Nipissing beach 
 
 75
 
 NE-SAW-JE-WON 
 
 Photo by Michigan Department of Conservation 
 
 PLATE 14.— GRAND MARAIS DUNES 
 
 ON THE NIPISSING BEACH OVERLOOKING LAKE SUPERIOR. 
 
 high above, and in the other depressed it below the present 
 water level. At Port Huron the Nipissing beach is 595 feet 
 above sea level; it rises to 631 feet on Mackinac Island, to 
 651 feet at Sault St. Marie, and to 710 feet at Peninsula 
 Harbour on the North Shore of Lake Superior. In early 
 Nipissing time the northern part of Keweenaw Peninsula was 
 an island, but Lake Nipissing built a bar across the mouth of 
 the separating strait, connecting the island to the mainland 
 and ponding the waters back into Torch and Portage lakes. 
 Man has cut a canal through the bar and reproduced the old 
 strait. 
 
 During the existence of the Nipissing lakes the water in 
 the St. Clair basin was at so low a stage that perhaps even the 
 swamps were drained by the sluggish river that flowed past 
 
 76
 
 THE NIPISSING GREAT LAKES 
 
 the site of Detroit to the small Lake Erie, which was then ten 
 to twelve feet below its present level. Submerged old river 
 channels can be traced in the western part of the Erie basin, 
 indicatini; the land conditions of Nipissing time. The bays 
 along the southern shore of Lake Erie are the drowned river 
 channels of this time. The caves at Put-in-Bay were all above 
 water during the Nipissing stage of Lake Erie, although now 
 parts of them are submerged. 
 
 During this time only the waters of the greatly-reduced 
 Lake Erie poured over Niagara halls and cut the narrow gorge 
 between the upper part of the Eddy Basin and the railroad 
 bridges — the three-fourths-of-a-mile-Iong gorge of the 
 Whirlpool Rapids. (Eigure 12.) Above the bridge the gorge 
 is wider, marking the beginning of the present Great Lakes 
 stage. 
 
 When uplift of the continent had changed the shore lines 
 and outlets of the lakes and the entire discharge of the Nipis- 
 sing lakes passed through the col at North Bay, the stage en- 
 dured for a long time. But the end came for the Nipissing 
 lakes as once again uplift in the north spilled the waters south- 
 ward. The old Chicago outlet was put in operation again but 
 for only a short time, for the lake level soon fell three or four 
 feet so that entire discharge was finally poured through the 
 outlet past Port Huron, reviving St. Clair River and spreading 
 the overflow into the St. Clair basin to form Lake St. Clair; 
 then the current quickened in the newl\ -formed Detroit 
 River. The waters of the broad shallow strait connecting the 
 Superior and Huron basins across the eastern end of the St. 
 Mary's peninsula were withdrawn into St. Mary's River, and 
 the two lakes become independent; Lake Superior was held 
 back in its higher basin b>' the rim of the old Cambrian sand- 
 stone "bowl," which crosses the river at the falls mu\ rapids 
 of the St. Mary's. So recently did this separation take place 
 
 77
 
 NE-SAW-JE-WO N 
 
 that the river has accompHshed little gorge-cutting and little 
 destruction of the rapids. 
 
 The Modern Great Lakes 
 
 When all the waters had ceased to flow through the North 
 Bay outlet and all finally poured southward to Lake 
 Erie, the present stage of the Great Lakes was begun. These 
 lakes, like their glacial ancestors, are building beaches, mak- 
 ing shore cliffs, cutting caves and arches in rocky headlands, 
 and deepening fjords — as along Isle Royale and Les Cheneaux. 
 In other places they are straightening shores by building bars 
 and spits across the bays, creating — as did Lake Nipissing 
 along the Lake Michigan coast — small lakes barred from the 
 large lake by dune-capped sand bars. Sands from their shores 
 are being piled by the wind high in dunes. Dunes along Lake 
 Michigan are as high as, if not the highest dunes in the world. 
 In places like the Sleeping Bear — on the Point of that name 
 on the northwestern coast of the Southern Peninsula of Michi- 
 gan — the dunes are perched atop the bordering moraine; in 
 other places they bury the Algonquin and Nipissing shores. 
 Down-cutting of the outlets continues, so that beaches lower 
 than the Nipissing have been made by the modern lakes. One 
 of these beaches, which is fairly strong and can be traced 
 around the lakes, is called the Algoma beach, from the place 
 where it was first noticed on North Channel of Lake Huron. 
 
 The connecting rivers of the Great Lakes also have had an 
 interesting and complicated history, as they developed with 
 the changing lakes. In order of age (in the present arrange- 
 ment of the lake-river system) these rivers are St. Clair, De- 
 troit, Niagara, Nipigon, St. Lawrence and St. Mary's. Nipi- 
 gon River is the largest tributary of Lake Superior and in its 
 lower course flows across the dry bed of old Lake Nipigon, 
 once the most northerly bay of Lake Algonquin. So many 
 
 78
 
 THE MODERN GREAT LAKES 
 
 features of the Great Lakes are unique, it is not surprising; to 
 lind that the delta of St. Clair River is most unusual, for it 
 is built by a stream flowing from one lake into another. 
 Earlier in the story we found that this river had to cut across 
 the Port Huron moraine, south of Port Huron, in order to 
 carry the waters of the glacial lakes. Thus the present river 
 acquired some tools which had been left in the channel when 
 the former stream became sluggish or disappeared. These, in 
 small amount, the present river has ground up, carried into 
 Lake St. Clair, and dropped when the current was slackened 
 in the quiet waters of the lake. The delta has been increased 
 in size — principally after all the morainic materials were car- 
 ried away — by sediments which have been washed by storm 
 waves from the Lake Huron shores. In the narrow southern 
 part of Lake Huron waves are cutting material from the 
 Canadian shore; the coarse material is deposited on the Cana- 
 dian side at Point Edward, but the finer is being carried by the 
 river to the American side, building the delta — the famous 
 St. Clair flats — farther out into Lake St. Clair. 
 
 The narrow part of Detroit River, between Belle Island 
 and Delray, is the part of its channel cut across the moraine 
 which separated the Erie and the Huron ice lobes and which 
 for a time held the waters of Lake St. Clair at a higher level. 
 At first the river flowed across the moraine in several chan- 
 nels, but eventually it deepened the present channel opposite 
 Detroit and drew all the overflow from Lake St. Clair through 
 one channel. Then for a time the river widened, as far 
 south as Crosse Isle, into small Lake Rouge which existed long 
 enough to build a distinct beach. Many of the older cottages 
 on Grosse Isle are built on the Rouge beach. South of Wyan- 
 dotte the river once entered Lake Erie through many chan- 
 nels or distributaries, and probably built a delta of the ma- 
 terials it washed from the broad flat moraine which it crosses 
 at Trenton. But lifting of the lake level has submerged the 
 delta front, and deepening of the river has drawn the water 
 
 79
 
 C/3 
 
 <: 
 
 < 
 Pi 
 < 
 
 < 
 
 H-l 
 
 80
 
 R i: V 1 1: w AN I) iM<i: VI t w 
 
 from all the western distributaries into twtj — the channels 
 around Grosse Isle — leaving the abandoned channels as curi- 
 ous depressions occupied by small creeks or as the natural 
 canals across Grosse Isle. 
 
 Since the establishment of the present lake s\su'ni, i\iai;ara 
 River, with the force of overflow waters from the lour upper 
 lakes, has cut the gorge over two and one-quarter miles — from 
 the railroad bridges to the Horseshoe Falls. 
 
 The Story Unfinished 
 
 Thus reads the story of the Great Lakes — descendants of 
 much smaller, higher, independent lakes which were outside 
 the present lake basins and discharged to the sea through 
 outlets leading to the Mississippi River, thence to the Gulf 
 of Mexico; which grew in size to lakes larger than the present 
 and found eastern outlets to the Atlantic, first by the Mohawk 
 and Hudson rivers and finally by the St. Lawrence — a 
 history and record of which there is no counterpart on the 
 globe. Through all the time man has been on the continent, 
 the lakes have exerted an influence on his life. The old outlets 
 served as highways and portages from one part of the country 
 to another; they were chosen as the sites of forts to guard 
 the frontier; they became the passes for railway, canal, and 
 concrete highway. The ancient beaches served as lines of 
 travel for red man and white, for trails and highways, for 
 roads of rail and concrete; they are the sites of all the forts 
 which commanded the Great Lakes. The lakes lured the early 
 explorers westward as they sought a route to India, served 
 as routes for trapper and fur trader and for the seeker of 
 precious metals, and finally, as the highways of a vast water- 
 borne commerce when the riches of their waters and their 
 borders became known. The old spillwa> s and lake beds be- 
 came the fertile gardens of agriculture. And not the least of 
 their significance, the shores of these lakes offer some of the 
 most magnificent scener>' in the world. 
 
 81
 
 NE-SAW-JE-WON 
 
 What of the future? Lakes are but ephemeral features of 
 any landscape. The Great Lakes, like all others, are doomed 
 to extinction. Slowly they are filling, slowly their outlets are 
 being lowered, and eventually they will be drained; but as 
 long as the rock sill at Buffalo holds — or until Niagara River 
 cuts back to Lake Erie — the upper lakes will remain as lakes. 
 Measurements of Niagara Falls since 1827 show that the 
 Horseshoe Falls are cutting back at the average rate of four 
 to five feet each year and no longer have the smooth horseshoe 
 curve at their crest which gave them their name. Until St. 
 Mary's River cuts through the Cambrian sandstone sill at the 
 rapids, Lake Superior will be held in its basin twenty feet above 
 Lake Huron. But when these rock barriers have been cut away, 
 the lakes will shrink in their basins and once again will become 
 a great river system. Then the records of these lakes also will 
 be shown by the beaches and shores they have made. 
 
 For a long time the land has been fairly stable; but occa- 
 sional slight earthquakes, the deepening of the waters on the 
 southern shores of the lakes, the withdrawal of water from the 
 northern shores — exposing the lake bottoms, and other evi- 
 dences, all show that uphf t has not ceased. Measurements indi- 
 cate that the North American continent is rising at the rate of 
 about one inch every ten years for each 100 miles north of the 
 Whittlesey hinge line. Will it rise high enough to spill the 
 lakes over the limestone sill at Chicago, which is only eight 
 feet above Lake Michigan, and return the flow to the Gulf of 
 Mexico ? Has the glacial period passed or are we in an inter- 
 glacial stage? Will the ice return and destroy all the evidences 
 by which this story is told? If this happens it will be so far in 
 the future — so many thousand of years — that another civili- 
 zation will write the story. 
 
 82