Page:Popular Science Monthly Volume 56.djvu/521

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FRAGMENTS OF SCIENCE.
507

they have tended toward economic forest management so far as their object was the continued use of the land for producing woods. Among the measures looking in this direction Mr. Pinchot mentions in his circular the practice which has been adopted "because it pays," in some of the spruce lands of the Northwest, of leaving the small trees standing, so that the lumbermen can return for a second crop earlier than would otherwise be possible; and the adoption by farmers of methods in getting their wood, for saving the best trees and promoting their growth and that of the new ones; of keeping sprout lands to be cut over regularly and systematically, for periodical renewal, and of tree planting on waste places, hillsides liable to be washed, and the banks of streams. Other forms of planting are the institution of wind breaks in the treeless West, and special plantations for fence posts, etc. A kind of forestry practice is likewise indicated in the special pains that are taken by farmers and in lumbering districts to lessen the danger of fires. Forester Pinchot desires that all the information that can be gained be communicated to him for the proposed article.

Professor Putnam on the Origins of the American Races.—In his address as retiring President of the American Association, Prof. F. W. Putnam, after expressing his high opinion of the late Dr. D. G. Brinton and his scientific labors, referred to the differences of opinion that had existed between them in respect to the origin of the American peoples, and proceeded to expound his own views on the subject. He regarded the term "mound-builders" as comprehensive enough to include all the peoples who had left the marks of their former presence in this country. Even the shell heaps could not be regarded as the work of one people. From the time of the earliest deposits—which were of great antiquity—to the present, such refuse piles had been made and many of the sites reoccupied, sometimes even by a different people. So with the mounds of earth and stone; many of them are of great antiquity, while others were made within the historic period, and even during the first half of the present century. These works were devoted to a variety of purposes, and there are many different kinds of them. Besides the mounds, there are groups of earthworks of a different order of structure, that must be considered by themselves—great embankments, fortifications, and singular structures on hills and plateaus that are in marked contrast to the ordinary conical mounds, and mounds in the form of animals and of man. The considerable antiquity of these older earthworks is proved by the accumulation of mold and the forest growth upon them. "If all mounds of shell, earth, or stone, fortifications on hills, or places of religious and ceremonial rites, are classed, irrespective of their structure, contents, or time of formation, as the work of one people, and that people is designated as the 'American Indian' or the 'American race,' and considered the only people ever inhabiting America north and south, we are simply … not giving fair consideration to differences, while overestimating resemblances." Citing analogies between our earthworks and Mexican structures, and looking upon the Pueblos as a connecting link, "we must regard the culture of the builders of the ancient earthworks as one and the same with that of ancient Mexico, although modified by environment. Our northern and eastern tribes came in contact with this people when they pushed their way southward and westward, and many of their arts and customs still linger among some of our Indian tribes. It is this absorption and admixture of the stocks that has in the course of thousands of years brought all our peoples into a certain uniformity. This does not, however, prove a unity of race.

Heat Insulators.—Mr. C. L. Norton has made experiments, at the request of Mr. Edward Atkinson, in order to determine the relative efficiency of several kinds of steam-pipe covering now on the market; to ascertain the fire risk attendant upon the use of certain methods and materials employed for insulation of steam pipes; to show the gain in economy attendant upon the increase of thickness of coverings; and to find the exact financial return that may be expected from a given outlay for covering steam pipes. A method of experimentation was adopted which repre-