The different periods to which the various mounds and burial places belong can only be made out by such a series of explorations as the museum is now conducting in the Little Miami Valley, and when they are completed we shall be better able to answer the question, "Who were the mound-builders?" than we are now. That more than one of the several American stocks or nations or groups of tribes built mounds seems to me to be established. What their connections were is not yet by any means made clear, and to say that they all must have been one and the same people seems to be making a statement directly contrary to the facts, which are yearly increasing as the spade and pick in careful hands bring them to light. That many Indian tribes built mounds and earthworks is beyond doubt, but that all the mounds and earthworks of North America were made by these same tribes or their immediate ancestors is not thereby proved. Mr. Carr, in his recent paper published by the Kentucky Geological Survey, has taken up the historical side of the question, but it must not be received for more than he intended. He only shows from historical data what the spade and pick have disclosed to the archæologist. It is simply one side of the shield; the other is still waiting to be turned to the light; and as history will not help us to read the reverse, only patient and careful exploration will bring out its meaning.[43] This, it is true, is but an incidental paragraph thrown into a report of the work of the museum, but I have selected it as the latest expression on this subject by one of our most active and practical American archæologists, and because it will furnish a basis for the remarks I desire to make on this subject. In order that the reader may clearly understand the particular points to which I shall call attention, I will introduce here a brief review of the leading opinions so far presented regarding the authorship of these ancient works. It was not until about the close of the eighteenth century that the scientific men of the Eastern States became fully impressed with the fact that remarkable antiquities were to be found in our country. About this time President Stiles, of New Haven, Dr. Franklin, Dr. Barton, and a few other leading minds of that day, becoming thoroughly convinced of the existence of these antiquities, and having received descriptions of a number of them, began to advance theories as to their origin. William Bartram had come to the conclusion, from personal observation and from the statement of the Indians that "they knew nothing of their origin," that they belonged to the most distant antiquity.