Page:Popular Science Monthly Volume 22.djvu/473

Rh the modern Indians as the lineal descendants of the mound builders, which is quite probable. Heretofore but three or four authentic skulls of the mound-builders have been found in any sort of preservation, while here we have a great many taken from a small area. Further, if we are to refer the cemetery to the mound-building race, we must admit that the race disappeared within a very recent period. On a level bank near the Little Miami River is a circular excavation about forty feet in diameter and seven feet deep. "An old settler relates that fifty years ago remains of stakes or palisades could be seen surrounding this excavation." These have since disappeared, but their being there shows within how recent a period the ground was abandoned. Then the age of the forest-trees growing on the ground argues against any very great antiquity. The largest trees measured are a walnut fifteen and a half feet in circumference, an oak twelve feet, an oak and a maple each nine and a half feet in circumference, equal to about five, four, and three feet in diameter respectively. Now, the average growth of fourteen different species of trees is about ·12 of an inch a year, or one foot radius (two feet diameter) in ninety-eight years. Taking this average, a tree five feet in diameter would be two hundred and forty-five years old; one four feet in diameter, one hundred and ninety-six years old; and one three feet in diameter, one hundred and forty-seven years old; or, in round numbers, two hundred and fifty, two hundred, and one hundred and fifty years respectively.

There is no evidence to show that there was any growth of forest on this ground, after its abandonment by the former residents, previous to the one now covering it. The roots of living trees having trunks two and three feet in diameter have been found penetrating the crania of skeletons found here, a tolerably sure indication of a first growth. Notwithstanding the assertions of many people to the contrary, the process of covering land with dense forest is by no means a slow one. A field allowed to go without being cultivated becomes in a few years covered with a new growth of saplings. Mr. Robert Ridgway, in a late paper, after referring to the cutting off of timber, and also to its encroachment on prairie-land in Illinois, says: "The growth of this new forest is so rapid that extensive woods near Mount Carmel [Illinois], consisting chiefly of oaks and hickories (averaging more than eighty feet high, one to nearly two feet in diameter), were open prairie within the memory of some of the present owners of the land." Taking this fact into consideration, and remembering that