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Show Simple and Cheap Scientific Experiments and Movements in Scientific Scien-tific Circles. INTEEESTING NEWS AMD NOTES. How a Plain Glass Tumbler Half Pull of Water Porms a Substitute for a Liquid Prism. Take a sheet of thick paper, cut a narrow slit through it, and hold it in tho sunlight so that the image of tbe slit shall be thrown npoa a sheet of white paper placed on a table beneath. At first only a bright . AN IMPROVISKD LIQUID rRISM. Image of the slit will appear; but If the tumbler, one-third full of water, held inclined in-clined at an angle as shown in the illustration illus-tration is placed in the path of the beam of light not only will the course of tbe beam as a whole be refracted or bent out of a straight lino, but the light itself will be more or less perfectly decomposed Into Its constituent colors, forming a miniature sol sr spectrum. Tho effect is rendered more striking by cutting two slits in the paper alongside of each other, so that the light passing through one goes direct to the paper screen below, while the other goes by way of t he Improvised prism. Although a dark room with an aperture for the light to enter is unnecessary in this experiment, Popular Scieuoe News explains that such an arrangement, where available, would be an improvement. By filling the air with a little smoke or dust the entire course of the beams may ho easily traced. ! Warnings of a Tornado. ! It would be a great advantage to all concerned con-cerned if peoplo could realize that the tornado tor-nado proper is an exceedingly definite and unmistakable phenomenon; that it docs not come upon a bouse like a stroke of lightning, unseen .and unheralded. Instances In-stances are by no means rare where tho funnel has been seen udvuneing directly over a person, and hits been easily avoided by running to the north or north-wast. north-wast. On tit south sitlo of tho path there are indraughts extending to quite a distance; so that it is generally safer, unless un-less the track of tho tornado is seeu to be '! quite to the north of the observer, for one to run to the northwest, but never to the northeast or tost, as that) is in the line of tho tornado. ,- ''. '., Persons have stood within ISO feet of the tornado on the north side, and huve felt no unusual disturbance. Itis admitted, however, how-ever, that this require no unusual courage. cour-age. Let the people of tho west look upon , this phenomenon more in' tho light of its great peculinrily. and wonderful nature a nature which has absolutely no parallel, and one Urn study of which must bo for years to come of the highest importance. The wisest philosopher has hardly begun to get un inkling of its formation; and thoso who are so mimtoU can, by a careful observation and record, help in obtaining and formulating the facts regarding this extraordinary appearance. Science. The 8111c Cotton Tree. I The tree depicted in the reprint here presented from Garden and Forest is a line specimen ot tho silk cotton tree of the West Indies, which botanists call erioden-dron erioden-dron nnfrauluotum. Tlio generic name is formed from two Greek words meaning wool and tree, and wus given to it on ae-count ae-count of tho brown wooly substance which surrounds the seeds, while tbe specific name, which means the bending in and eut - of a road or path, wus bestowed upon the tree on accouut of its great size, which made it easier to divert a road round the trunk than to cut down the tree. Tho specimen hero illustrated stands in front of the town house of Nassau, where it was planted probably in the early days of tho settlement of the island, as the branches have attained a spread of 150 feet, while a man walking round the buttresses which support the trunk, aud which are' 1 well shown in our illustration, must make fifty paces. The silk cotton tree is the largest larg-est inhabitant of the Caribbean foreats. Tho fruit is a large, woedy, round, obtuse capsule, consisting of five cells and split- THE SILK COTTON TREE AT NASSAU. ting open by five valves, each cell coutain-hig coutain-hig a number of broad seeds surrounded by dark brown cotton simihirtU character to that at the cotton plant, which botan-ically botan-ically is nearly rolated to this tree. Tbe silk cotton tree grows very rapidly. Its imposing siss and great beauty, aud possibly the belief that the woolly appendage append-age of the seed might prove of greater value than it has turned out to be, attracted attract-ed the attention and excited the wonder of traveler in the early days ot the discovery of the New World. Oviedo y Valtles, who lnndcd in San Domingo iu 1514 and wrote the earliest account of the natural history of America, was the first author to mention men-tion it, und from Oviedo s day to the present pres-ent tbe silk cotton tree has been described more or less in detail by every author who has written of the natural features and S reductions of the West Indies and the panish main. |