Page:The American Cyclopædia (1879) Volume XI.djvu/622

604 MINNESOTA waters of the Des Moines, about 135 m. long, of which about 20 are navigable. All the riv- ers have numerous branches, which are not navigable. The navigable waters within the state have a total shore line of 2,746 m., and a water line of 1,532 m. Along the banks of the Mississippi and of some other rivers are high bluffs, forming one of the most interest- ing and characteristic features of the scenery. Minnesota is distinguished for the number and beauty of its lakes. They have been esti- mated as high as 10,000 in number, and are from 1 m. to 30 m. in diameter ; and many of them have an area of from 100 to 400 sq. m. Their waters, generally sweet and clear, abound in fish. The largest are the lake of the Woods, Rainy, Namekin, Bois Blanc, Vermilion, Swan, Sandy, Winibigoshish, and Leech lakes, and Mille lacs in the north and northeast, Red lake in the northwest, Big Stone, Benton, Sauk, and Swan in the west and southwest. Notwith- standing the great area covered by this state, its rock formations, so far as they have been ex- plored, appear to be limited almost exclusively to the azoic and lower protozoic groups ; and over the greater part of the state these are concealed beneath the diluvial deposits which make the superficial covering of the rolling prairies. The N. W. coast of Lake Superior is made up of metamorphic slates and sandstones, intermingled with grits of volcanic origin and other bedded traps and porphyries. These are intersected by frequent dikes of greenstone and basalt ; and among them are occasional deposits of red clay, marl, and drift. Behind this group are traced westward, along the northern boun- dary of the state, formations of hornblende and argillaceous slates, succeeded by granitic and other metamorphic rocks. These groups extend S. W. into the central portions of the state. Along the southern boundary the Devonian formation is found in the extreme west ; the Ni- agara limestone succeeds this toward the east, and next occurs the Galena limestone, and then the Trenton limestone and the upper or St. Peter's sandstone, which overlies the Potsdam sandstone. These sandstones crop out up the valley of the Mississippi, nearly as far as Fort Snelling, where the lower Silurian limestones, which on both sides of the river lie behind and over the sandstones, meet in the valley and form the bluffs of the rivers. They are traced up the Minnesota river, curving round and al- most reaching the southern boundary of the state again, and cutting off the continuation of the higher groups further northward. Thus throughout the state there appears to be no room for the carboniferous group. The lead- bearing rocks traced from the Iowa line are limited and of little importance. It is believed that the Jf. E. corner of the state will prove a valuable mineral field. Copper abounds in the mineral belt stretching along the N. shore of Lake Superior, and masses of the pure metal have been taken from Knife and Stuart rivers. Iron ore of good quality is found in considerable quantities around Portage and Pigeon rivers. Large deposits of peat exist in all parts of the state. In the Red river valley are extensive salt springs. Slate, limestone, sand for glass, and clay are also found. The existence of gold and silver on the shores of Vermilion lake has been shown. A geologi- cal and natural history survey of Minnesota is now (1875) in progress, under the direction of N. H. Winchell, state geologist, and S. F. Peckham, state chemist, professors in the state university, to which institution the survey has been intrusted by law. Up to 1875 a prelim- inary report and two reports of progress had been printed in the annual reports of the board of regents for 1873-'5. The soil is fertile, two thirds of the surface being well adapted to the cultivation of all the cereals and roots of the tem- perate zone. It is composed generally of a dark, calcareous loam, abounding in organic and saline ingredients, and is retentive of moisture. The climate of Minnesota is pleasant. The winters are cold, but clear and dry, and the fall of snow is light; the summers are warm, with breezy nights, during which occur most of the rains ; and the general purity of the air and salubrity of its climate recommend it for the residence of invalids. The following summary for 1874, reported by the United States signal bureau, is for St. Paul, lat. 44 53', Ion. 93 5': THEHMOMETEK. Total MONTH. Mean barome- rain- fall, Prevailing wind. Maxi- Mini- mum. mum. Mean. ter. inches. January... 48-00 -23-00 18-85 80-073 0-49 Southeast. February- 86-00 -18-00 14-40 80-082 1-07 Southeast. March.... 46-00 -5-00 28-66 30-030 2-241 North west. April 71-00 7-00 87-52 80-008 95 ; North. May 94-00 81-00 62-24 29-860 1-65 North. June 94-00 42-00: 68-70 29-797 11 -67 Southeast. July 99-00 53-00 74-72 29-842 1-94 Southeast. August.... 91-00 54-00 ! 70-54 29-892 8 -90 Southeast. September 92-00 87-00 60-95 29-908 5-76 Southeast October .. 74-00 21-00 49-30 80-008 8-21 Northwest. November 72-00 - 8-00 28-72 29-951 1-90 Southeast. December. 48-00 -20-00 18-81 80-648 0'72 Northwest. Mean... 71-67 14-25 48-62 30-490 85-50 Southeast. The country, especially above lat. 46, is well timbered ; pine forests extend far to the north, and birch, maple, aspen, ash, and elm abound. A large forest of hard-wood varieties, known as the Big Woods, and called Bois Franc by the early French settlers, extends over the central portion of the state W. of the Mississippi, and covers an area of about 4,000 sq. m. On the river bottoms are found basswood, elm, aspen, butternut, ash, birch, maple, linden, balsam fir, and some oaks; and in the swamps tamarack, cedar, and cypress. Among the wild animals are the elk, deer, antelope, bear, wolverene, otter, muskrat, mink, marten, raccoon, and wolf. Of birds, there are the golden and bald eagles, grouse, partridge, hawk, buzzard, owl, quail, plover, lark, and many smaller kinds. There are also the pelican, tern, shel- drake, teal, loon, wild geese, wild ducks, and other water fowl. The waters contain pike,