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EVOLUTION that the higher animals have been derived gradually from simpler ones, including with the higher animals, also, the body of man. The very general acceptance of this view in the latter part of the 19th century, under the title of the doctrine of evolution, has made an epoch. It has had great influence, perhaps the greatest of any one doctrine, in modifying the point of view in many fields of thought. It is, therefore, so important that all intelligent people ought to know what the doctrine is. By way of clearing the ground it may be repeated that it is not a question of creation through Divine agencies or non-creation, but a question of method of creation. It is not a theological question, but an historical one. Nevertheless, when the doctrine arose with new force about 1860, it found itself in conflict with theological ideas and especially with the doctrine of creation called special creation. It is natural to think that the latter was a view held by the early theologians and Fathers of the church, but it is instructive to find that some of them, such as St. Augustine, openly expressed the opinion that God created all things “in the germ.” The doctrine of special creation was introduced into English Protestant thought through the epics of John Milton, to whose forceful and picturesque language we have been indebted for many of our accepted dogmas, without having paused to examine into them.

The question of the parentage of animals involves the distant past. The very center of it is this: Are species fixed and permanent, as Linnæus, the great Swedish botanist and naturalist, supposed; or do they change? If it can be shown that species (or particular kinds of animals and plants) change so much as to be recognized as different kinds, then there has been evolution. If, on the other hand, the evidence shows that species are fixed, there has been no evolution. It is well-known that by cultivation we can produce varieties of flowers, and by breeding we can produce different kinds of pigeons, fowl, and stock. Therefore, living beings may change through changes in their surroundings. But we must bring the history of past ages to bear upon the question. Fortunately there are preserved in the rocks the petrified remains of animals, showing their history for many thousands of years, and we may use them to test the question. It is plain that rocks of a lower level were deposited before those that cover them. Now, in Slavonia we have some fresh-water lakes that have been drying up from geological times. All through the ages these waters were inhabited by snails, and the first formed ones were parents of the later broods. As the animals died, their shells fell to the bottom and were covered by mud and débris, and held there like currants in a pudding. In the

course of ages these layers thickened and were changed into rock, and thereby we have shells preserved in their proper order of birth and life, the most ancient ones at the bottom and the newest at the top. We can sink a shaft or dig a trench, and collect the shells and preserve them in proper order. Those nearest the top are descended from those near the bottom, but are very different. No one would hesitate to name them different species, in fact naturalists made six or seven different species when these shells were first examined. If, however, the whole collection were laid out in a long row in proper order, while those at the ends would be very different, if we begin at one end and pass to the other, the shells all grade into one another by such slight changes that there is no line showing where one kind leaves off and another begins. This shows their history for thousands of years: The species have not remained constant, but have changed into other species. We have other examples of similar conditions in Württemberg, which show that shells may change not only into different species but into different genera so gradually that one cannot tell where to separate one kind absolutely from another. But we have more perfect and more remarkable series than those mentioned, involving higher animals. For example, there is contained in the rocks of our western states the complete history of the horse-family—written as it were on tablets of stone—and extending over a period of more than 2,000,000 years. Geologists can, of course, measure the thickness of rocks and form some estimate of the time it took to have them deposited, for the rocks that lie in layers or strata were deposited layer by layer, usually by water. In the deposits near the surface we can find remains of the immediate ancestors of the horse of to-day, and there is but little change. In lower rocks we can come upon the forms from which these were derived, and so on, as long as the record holds out. If in this way we go into the past a half-million years, we find the ancestors of the horse reduced in size and with three toes on the fore and hind feet. The horse has now only a single toe on each foot, but small splint-like bones that represent the rudiments of two more. If we go back 1,000,000 years, we find three toes and the rudiment of a fourth, and, going back 2,000,000 years, we find four fully developed toes and bones in the feet to support them. It is believed that in still older rocks a five-toed form will be discovered, which was the parent of the four-toed form. To sum up this evidence: The parentage of the horse is surely from animals with four (and possibly five) toes, not like the horse of the present day. Therefore, horses have been evolved, not originally created as we