IOWA HISTORY PROJECT |
STORIES OF IOWA
FOR
BOYS AND GIRLS
CHAPTER I
IOWA IN THE BEGINNING
Did you ever wonder what Iowa was like in the days of long ago, before any white man had come to this region? Of course there were no houses here, nor telephone poles, nor railroads, nor cities, nor even any roads. Then only the Indians and the wild animals lived in what is now Iowa.
But the story of Iowa began long before any Indians lived here. Once upon a time, long, long, long ago, all Iowa was under the sea. During this period there were millions of little shell-covered animals living in the shallow parts of the ocean. As they died they sank to the bottom and slowly, shell by shell, layers of limestone were formed. Have you ever seen ledges of limestone along the rivers or creeks in your part of Iowa? In many places throughout the state this limestone is quarried and used for buildings or bridges; or it is crushed to be used in road making or burned to make lime for plaster.
At one time when the sea had receded somewhat, part of Iowa was above the surface of the water. In those days rivers brought great loads of clay and sand down from the north, and left them in the shallow water near the shore line. After a long time the sand hardened into sandstone and the clay into shale. Have you ever seen the beautiful beds of colored sandstone near McGregor? If you look carefully into some of these beds of limestone, sandstone, and shale you will find little shells or fossils. These show what kind of animals lived at that time.
During all the years that part of Iowa was above sea, water from summer storms trickled through the rocks and dissolved tiny particles of lead. These were carried into the cracks and crevices of the limestone, and formed the veins of lead ore in the region near Dubuque. Later on in this book you will read how the Indians used to dig out this lead and sell it to traders, and how the first white settler in Iowa came here because he wanted to mine the lead.
These came in a time when the sea drew back to the south. In those days the climate was warm and moist. Giant trees, enormous ferns, and tall rushes grew in the swampy region of south-central Iowa. As they died they fell into the water. Centuries passed, and in time these swamps were filled with clay brought down by the rivers. In time the layers of trees and plants were squeezed and pressed until they became coal. The clay above them hardened into shale or slate. Have you ever seen any of the coal mines in Iowa?
Again the surface of the earth changed, and here and there in Iowa inland seas were formed. As the water in these evaporated, deposits of gypsum remained in some places. Gypsum is a soft, gray rock used for plaster or stucco. Do you know that Iowa has one of the richest gypsum beds in the United States? In Webster County there are sixty or seventy square miles of land underlaid with gypsum beds from twenty-five to thirty feet thick.
Many years after the coal in Iowa was formed and the minerals laid down, the climate in North America became so cold that the snow which fell in winter did not melt in summer. What is now Canada became covered with a great sheet of snow more than a mile in thickness. In time the whole mass turned to ice. Then it began to move slowly southward. Wherever the soil was loose to move slowly southward. Wherever the soil was loose it scooped it up and carried it along.
As this huge ice sheet moved southward across Iowa it planed off the hills and filled up the valleys. Streams were turned out of their courses, rocks were crushed to fragments, and these fragments were ground into powder. Can you imagine all of Iowa covered with a sheet of ice half a mile or more deep?
After a time the climate again became warmer and the ice began to melt slowly. Gradually all of Iowa was uncovered, and on its surface remained the powdered rock, pebbles, and boulders brought by the ice. This glacial drift, as the soil which the glacier dropped is called, formed hills and ridges in some places. In others it was spread out evenly.
The first glacier was followed by a long period of temperate climate. But the ice age was just beginning. Again and again the glaciers crept down from the north, twice over all Iowa, and on three other occasions covering part of the region. As each ice sheet melted it left its deposit of powdered rock, which mingled with the muck of the periods between the glaciers to form the rich soil of Iowa.
Of course no man lived in Iowa during the period of the glaciers, but the record of what happened is written clearly in the rocks and soils themselves. During the long years between the glaciers plants grew again, and strange animals - curious wild horses, elephants, and those huge animals of the very long ago, called mastodons - roamed over the fields and along the streams. We know these animals were here because fossil bones have been dug out of gravel pits. Have any such remains ever been found in your county?
When the Indians first came to Iowa is not known, but of course it was long after the last glacier had gone. They found the rivers teeming with fish, the forests full of animals, and herds of deer and buffaloes on the prairies. The prairies must have been beautiful in those days. For miles they stretched away with little dips and rises, covered with tall grass that rippled in the wind like the waves of the sea. In the spring and summer they were bright with many flowers, and in the autumn they were like a sea of brown and gold. This was Iowa before the white man came.