FOSSILS—EVIDENCES OF EARLY ANIMAL AND PLANT LIFE—GEOLOGICAL AGES—ROCK FORMATION—GLACIER PERIOD—MINERALS.

The oldest citizens of Atchison county are the animals and plants whose fossil remains now lie buried in the solid rocks. These denizens of long ago, by their lives, made it possible for later and better citizens to live and flourish in the happy and contented homes of her best citizens of the present day. Long before man ever saw Atchison county—long before man lived anywhere upon this earth, the seas swarmed with animal life and the dry lands supported a fauna and a flora substantially as great as those of the present time.

In character the animals and plants of those early days were very different from those of the present time. Almost all of their kind long ago became extinct. It is only the few who have living representatives anywhere in the world today, and they are degraded in form and size as though they had long outlived their usefulness. Some of the animals live in the waters of distant oceans, such as the brachiopods and other shell fish; the crinoids or sea lilies, and others of like character. On the dry land we find a few insects of the cock-roach type and other creeping things which inhabit dark and damp places, animals of gloom on whose forms the sunshine of day rarely falls.

The plants, likewise, are degraded in size and form. The modern bull-rushes of our swamps are descendants of ancient giants of their kind which grew to ten or twenty times the size of their modern representatives. The little creeping vines sometimes found in the shaded forest are lineal descendants of the mighty trees of the forests in the long ago while materials were gathering for the rock masses constituting Atchison county.

In order to converse rationally about geological time it has been found most convenient to divide time into periods in accordance with great natural events, and to give a name to each period that in some way expresses something desirable to be known and remembered. Usually geographic names of areas where rock masses are exposed to the surface of the ground are chosen, or some favorite geographic term may be used, and in rare instances some quality name expressive of the character or composition of the rocks.

Following the best usage of geologists the rocks exposed at the surface all belong to the age known as the Carboniferous, which lies at the top of the Palaeozoic, or ancient life rocks. The Carboniferous is divided and subdivided into a number of divisions, the lowermost of which has been named the Mississippian on account of their great abundance throughout the Mississippi valley. Above the Mississippian we find a mass of alternating beds of shale and limestone and sandstone aggregating about 2,500 feet in thickness, called the Pennsylvanians, a term borrowed from the State of Pennsylvania, where rocks of the same age so abound. Rocks formed during the remainder of geologic time are not found in Atchison county, except the covering of soil and clay so abundant throughout the county. An old-time name for the Pennsylvanian rocks is the coal-measures, a term now on the decline because the newer names—well, it is newer.

It appears that from the close of the Pennsylvanian time to the present Atchison county has been dry land. At one time, quite recently, as geologists reckon time, climatic conditions changed so that the snow falling during the winter could not be melted during the summer, so that to the far north great quantities of snow and ice accumulated and gradually spread over the surface of a large part of North America. One limb of this ice mass moved slowly southward and covered all of Atchison county, and much adjacent territory, and brought with it vast quantities of soil and clay and gravel that the ice sheet, as a great scraper, picked up from the surface as it came along. When the ice finally melted this debris was left, like a mantle of snow, covering the entire surface of Atchison county.

The rocks of Pennsylvanian age have within them much of value economically. Here and there inter-stratified with the sandstone and shale are large and valuable beds of coal, as is abundantly shown by the drilled wells and coal shafts within the county. It is probable that almost the entire county is underlaid with this same bed of coal, and if so it is worth substantially as much to the county as is the surface soil. It lies at so great a depth that it may be mined without any danger whatever of disturbing the surface.

The large amount of good hard limestone in the county guarantees an everlasting supply of stone for road making, railroad ballast, crushed rock for concrete works and all other uses to which such limestone may be put. With the Missouri river on the eastern boundary carrying unlimited amounts of sand Atchison county is well supplied with every material needed for unlimited amounts of mortar construction of all kinds. Recently, since Portland cement construction has so effectually replaced stone masonry, this becomes a very important matter.

Should market conditions ever become favorable it is also possible to manufacture the best grades of Portland cement by properly combining the limestones and shales of the county. Their chemical and physical properties are admirably suited for such purposes.

There is a possibility that somewhere within the county oil and gas may be found by proper prospecting. As no search for these materials has yet been made it is impossible to say what the results might be. Atchison county, however, lies within the oil zone that has been proven to be so much farther south, and until proper search has been made no one can say that oil and gas cannot be found here also.