Page:The World's Most Famous Court Trial - 1925.djvu/243

Rh buried animal and plant remains has been taught in this state since 1828, at which time Gerard Troost, one of the founders of the Philadelphia Academy of Science, was elected professor of geology at the University of Nashville, and three years later was elected state geologist of Tennessee. From that date to the present time, this science, dealing with the age and study of the earth, and its rocks and the buried LIfe which they contain, has been continuously taught in Tennessee.

Such teaching could not have been carried on through ninety-seven years of time, unless the teaching of evolution had been permitted as it was permitted by our religious ancestors who formed this state.

We know that streams and rivers carry sediment; that muddy waters Tennessee river, into the Mississippi are full of the soil of some field, washed into a nearby stream by a hard rain, and some such soil, when it once gets into a stream, starts on a long journey to the ocean. Most of the streams in this section are muddy for many months in each year, and this mud, which is the soil washed from our gullied hillsides, in this particular case goes down the Tennessee river, into the Mississippi river and to the Gulf of Mexico.

We know that at the mouth of the Mississippi river the sediments brought down by this river are deposited so rapidly that land is formed which is extending into the Gulf of Mexico at the rate of many feet a year. As a rule, these processes of weathering of rocks to produce soil, of erosion of this soil, and of deposition of this transported soil through rivers into some nearby sea or ocean, takes place so slowly, as time is generally measured, that we can only see through detailed and scientific observation the results within our own lifetime. But at the delta of the Mississippi river this very process is taking place so rapidly that anyone can easily measure it year by year and can understand that these same processes have been taking place all through all geologic time, and in each and every part of the world.

We also know that practically all of the earth has at some time or other been covered by water, and in these ancient seas life has existed, which has left its record to us in fossil form. It must, however, also be understood that large parts of our present water areas were at some period in past geologic time also land areas. These seas have come and gone over limited areas of the earth's surface many times during the geologic history of the earth.

We know that originally the mouth of the Mississippi river was near Cairo, Ill. and that all of the Mississippi valley, as we now know, it was at that time (which was the close of the Cretacious period) a part of a much larger Gulf of Mexico than the one that now exists. All of West Tennessee, during this time, was in a northern extension of the Gulf of Mexico, and the fine China clay deposits of that section were laid down in shallow water at the time tropical plants flourished in that section.

East Tennessee is made up of many layers of rocks, limestone, shale and sandstone, all of which were likewise laid down under water, and many of these layers contain the remains of animal and plant life. Some of the oldest rocks which contain animal life are found in East Tennessee. They are known as Cambrian rocks, and in these rocks occur the first abundant remains of sea form of life. This was the age of the early invertebrates. These rocks are well exposed to the cast of Dayton in the East Tennessee valley region.

Then came the time interval which the geologist calls the Ordovican, the time when primitive fishes, corals, and land plants came into existence. Sonie of these first corals in fossil form have been found in the western edge of Dayton. This time interval was followed by another series of rocks which, in East Tennessee, contain the red iron ore deposits which