SCIENCE SIFTINGS

New Zealand Tablet, 6 November 1919, Page 46

SCIENCE SIFTINGS

(By - “Volt.”)

Camouflage an American Indian Art. That the art of camouflage as now practised is an ' American institution and originated by tlxp American Indians •is the latest suggestion, according -to th e Scientific . mencan. It is asserted that the Indian children were aught to place flowers in their hair as well as twigs, leaves and other bits of foliage, and that they were able to move along the ground in such a stealthy manner that they were ' not discernible to the rest of the tribe. Before a young Indian could become qualified as a warrior he had to make ms approach to the Indian camp almost in the midst of the assembled warriors without being detected. The real origin of paint on the faces, as well as on the ‘ wigwams and horses, was apparently in the desire to make the : Indian blend with the rocks, trees, and dirt, so that he. could approach his prey or remain hidden without detection. ...--..1 Ancient Saws. ■. r ■ •i/j. The saw is the earliest tool that has been traced in * Egyptian history. It was found first in the form of a'"’ notched Bronze knife in the third dynasty, or about -5000 J ears before the Christian era, and was followed - in the fourth and fifth dynasties by larger-toothed saws, which s were used by carpenters; but there are no dated specimens ' ’ until the seventh century before the Christian era, when the Assyrians used iron saws. The first knives on record were made out of flint, and were in fact saws with minute s teeth. They probably were used for cutting up ' animals, as the teeth would break away even on soft wood. Rasps,-A which are but a form of saw, were first made of sheets of bronze punched and coiled round, but the Assyrians in the seventh century used the straight rasp, which specimens still in evidence show to have been made of iron, similar to the modern type. \ -tjjisvV Seeing the Earth’s Shadow. -h t/i Everyone is familiar with the shadow of the earth' as :v it appears when the moon is eclipsed, but not' many know * that they can see the shadow at less rare intervals much " nearer home. All that is necessary is a clear sky at 1 sunrise or sunset, for then the shadow falls upon the dust - ■ of our atmosphere in a most noticeable and striking manner. If you look eastward as the sun sinks behind the western horizon, a broad band .of red seems to appear opposite the sun. It merges into a yellow glow above, and that in turn blends into the blue of the zenith. As the red band rises, the under side of it fades into a -dull slate grey, the umbra of the shadow. The observation obtained from a position that gives a clear sweep of the horizon discloses the form of the shadow band as an arch, the crest of which is directly opposite the sun. ■ The more depressed the sun is beneath the horizon, the higher the arch towers toward the zenith. ’ As it rises it becomes less perceptible, until the red band that borders it on top spreads overhead in a rather weak glow. Astronomy’s Moral Value. The Rev. Father A. L. Cortie, S.J., the distinguished astronomer of Stonyhurst College, addressing the Liverpool Rotary Club on “The Value of Astronomy in Education,” said the war had taught us the necessity of having more science taught in our schools — so much specialised science as generalised science, among which he advocated the inclusion of astronomy. It was a curious tiling that the modern schoolboy knew loss about astronomy than did the schoolboy of the Middle Ages. While he did not advocate that boys and girls should be taught sufficient to enable " .-, them to become experts in astronomical lore, he thought ' everybody should know something about the motions of’ the V/. moon, the sun, and the planets, and about the chief constel- , ' rations. He felt this could be done without adding to an . already overcrowded syllabus by putting more astronomy i into the geography lessons, or by substituting for some of the arithmetical problems set by the mathematicians some astronomical questions which were most interesting to boys. The study of astronomy encouraged, observation and in- A. quiry, but its chief value in education was its moral value. There was no real education unless they had moral education, and astronomy, because of the order and beauty and magnificence which they observed in the skies, at once raised people’s minds to- things that were above, the, earth.