Within the area we have thus defined are located the works of the people we call the Mound Builders. What we wish to do is to learn all about these vanished people. A great many scholars have written about them, and large collections of the remains of their handiwork have been made. There is, however, a great diversity of opinion respecting the Mound Builders and their culture. So we see we have a difficult subject to treat of. In order to gain a clear understanding of it, we must describe the remains more closely. About all we can learn of these people is from a study of their monuments. We can not call to our aid history or tradition, or rock-carved inscription, but must resort to crumbling mounds, broken down embankments; study their location, and observe their forms. To the studies in the field we must add those in the cabinet, and examine the many objects found in and above the mounds and earth-works, as well as the skeletons of the builders of the works. Rightly used, we can draw from these sources much valuable information of the people whose council-fires blazed all along the beautiful valleys of the Ohio and Mississippi rivers in times far removed from us. Mound and Circle. We will first speak of the simplest form of these works, the ordinary conical mound. This is the one form found all over the extensive area designated. They exist in great numbers on the banks of the upper Missouri, as well as the river bottoms of the South. This cut represents a very fine specimen of a mound, in this instance surrounded by a circular embankment. We must not forget that mounds are found all over the world. “They are scattered over India, they dot the steppes of Siberia and the vast region north of the Black Sea; they line the shores of the Bosphorus and the Mediterranean; they are found in old Scandinavia, and are singularly numerous in the British Islands.”16 The principle in human nature which leads to the erection of mounds is living and active to-day. The shaft which surmounts Bunker Hill is but a modern way of memorizing an event which in earlier ages would have led to the erection of a mound, and the polished monument which marks the resting place of some distinguished man was raised for the same purpose as the mounds heaped over the chiefs and warriors of another age. The feeling which moves us to crown with steeples or spires our houses of worship is evidently akin to that which induced older races to erect a mound on which to place their temples, their idols, and altars of sacrifice.