ling to most people; but, as has been time and again conclusively shown, it is no unwarranted fancy. We are apt to consider the mastodon as a creature of so distant a time in the unrecorded past, that man must necessarily have appeared much later upon the scene. The truth is, comparatively speaking, the creature so recently became extinct that, in all probability, our historic Indians were acquainted with it. Certain it is that, in the distant long ago of the great Ice age, the mastodon existed, and equally certain that with him lived that primitive man who fabricated the rude implements we have described. The bones of the animal and the bones and weapons of the man lie side by side, deep down in the gravels deposited by the floods from the melting ice-sheet. In February, 1885, I walked to and fro over the frozen Delaware, where it reaches a full mile in width, and saw at the time many horses and sleighs passing from shore to shore. I recalled, as I walked, what the geologists have recorded of the river's history, and it was no wild whim of the unchecked imagination to picture the Delaware as a still more firmly frozen stream; so firmly ice-bound, indeed, that the mastodon might pass in safety over it—not cautiously, even, but with the quick trot of the angry elephant—and picture still further a terror-stricken Stone-age hunter fleeing for his life.
Just as our brief yearly winter gives way to milder spring, so, as the centuries rolled by, the mighty winter of the Ice age yielded to changes that were slowly wrought. Century by century, the sun's power was exerted with more telling effect; constantly increasing areas of northward-lying land were laid bare, and the forest followed the retreating glaciers' steps. This great but gradual change had, of course, its influence upon animal life, and many of the large mammals that have been named appear to have preferred the cooler to the warmer climate and followed the ice-sheet on its northward march.
In the unnumbered centuries during which these changes came about, man increased in wisdom, if not in stature, and the rude implements that characterize the lowest known form of humanity—palæolithic man of prehistoric archæology—were gradually discarded for smaller and more specialized ones. This change was doubtless the result of faunal changes that required a compound instead of a simple implement, as an effective weapon—a small spear-head attached to a shaft, instead of a sharpened stone held in the hand; and we find now, as characteristic of conditions geologically later than the gravel beds, a well-designed spear-point, larger than Indian arrow-heads, of a remarkably uniform pattern, and which might readily be supposed to be the handiwork of the historic Indians. But let us examine into the history of these objects a little closely. In the first place, the conditions under which