In addition to the Mounds and Earthworks, the Mound-builders left behind them many burial grounds or cemeteries, and numerous village or town sites. Usually the two are found together, and often the burial mounds are near-by. In the village sites there may be found, usually beneath the plow line in cultivated fields, the remains of rude streets, house foundations, fireplaces, and countless numbers of relics lost or thrown aside by the residents of the site, centuries ago. From these relics a good idea of the people and their life may be gained through study. Some of the principal village-sites and cemeteries explored by the Ohio State Museum are the Baum and Gartner sites, in Ross County, and the Feurt village-site, in Scioto County. The largest of all the Ohio village sites is known as the Madisonville site, located near Cincinnati. [Illustration: Fig. 5—The Great Serpent Mound, Adams County, Ohio.] Certain prehistoric remains of great interest are the Effigy Mounds, so-called because they were built in the effigy or image of birds and animals. The finest of these in Ohio is the Great Serpent Mound, of Adams County. Another interesting effigy mound is the Opossum Mound, near Granville, Ohio. The Effigy Mounds are believed to have represented the totems or clan symbols of their builders. Thus the Great Serpent Mound may have been the totem of the Serpent or Snake tribe. They also very likely played a part in the religion of the people who built them, as most primitive people appear to worship natural objects. Although most of the Effigy Mounds are found in southern Wisconsin, the Great Serpent Mound is the largest and finest known. THE ARCHÆOLOGIST AND HIS WORK All that we have seen and learned of the Mounds and Earthworks, up to this point, is merely what anyone, by using his eyes, might see and learn; in fact, just what the pioneers observed. In other words we have looked at them from the outside, without knowing the secrets buried inside them. And now, since the Mound-builders left no written history behind them, we must get acquainted with another branch of science in order to obtain the information we desire. This new science is known as Archæology, and the man or woman who works at it is called an archæologist. Archæology is really the science of old things; that is, it concerns itself with the things which human beings did before they became intelligent enough to write and leave behind them their own histories. Since he has no intentional records to guide him, the archæologist depends mostly on exploration or digging into ancient ruins and remains for his information. Thus he finds the rude relics of by-gone ages, relics lost or thrown away by their one-time users, and from these he pieces together the story of a people.