SCIENCE AND ART.

New Zealand Herald, Volume XXI, Issue 7002, 26 April 1884, Page 4 (Supplement)

SCIENCE AND ART.

Italian, scientists have recently been investigating with the microscope the origin of the showers of sand and meteoric dnst generally which fall in Italy, and especially in Sicily. The results show that the sand comes from Africa, where it is raised by the oyclonas, and carried into Italy and Sicily by tHe strong south-east and south-west winds. Dr.- Clevenger writes in the American (aturslist to show the disadvantages of the ;pright position in man. He shows that .'.othing but the original " all-fours" position, jom which he sprung, will account for the •jccnrrence of valves in the intercostal veins, &C, the absence of valves from parts where they .are .needed, such as the venoe cavce, &c, and the exposed and dangerous position of the femoral artery v All of these facts are fraught with a certain amount of danger to man in the upright position, but they are beautifully adapted to the quadrupedal. With so many drawbacks to the upright position," it is singular that man ever assumed it. But perhaps he thought it worth risking a little to obtain it.

Professor Milne, of Japan, who has already distinguished himself by his original observations concerning earthquake phenomena, has jußt published an important practical paper on " Earthquakes and Buildings." The hints contained iu it ought to be studied by all who are concerned with achitecture in countries, affepted by earthquake disturbances. Mr. Milne recommends that a house built in such-places, to be aseismic (that is unaffected by earthquakes), should be a low frame building, with iron roof and chimneys supported by'a number, of slightly concave surfaces resting on segments of stone or metal spheres, the"' latter being in connection with the ground.,.. The streets ought to be .wide in earthquake towns and open spaces left for refuges. Chimneys with heavy topsi like heavy roofs, should be avoided. . The pitch of "the roofs must not be too great. If it is necessary to have substantial buildings, their upper portion"ought to be as light as is con-, sisten't with the requisite strength., The city'of Manilla has .been re-erected much upon this plan, and now presents a singular appearance '. of light roofs rising from old foundations. . A-French scientist, M. Duchatre, has just published an account of some experiments he has been making with seeds. Everybody is aware of the influence which direct sunlight has upon the growth and development of 'young plants. - Well, M. Dnohatre has.been experimenting upon the sprouting and germination "of seeds with moonlight instead of sunlight... He subjected. the seedlings of lentils, vetches, &e., to its influence. When the seeds had sprouted he put them in a dark place,' and' kept them there for a time, so that their stalks grew slender and of a yellowish white. Afterwards, on ] three nights -when there'was clear'moonlight, he exposed them to,its.influence for six hours each night. He found. that the stalks at once became selenibtropio-rthat is, they turned towards and followed the moonlight, just as many plants, such as'the sunflower, are heliotropic, or.turn towards and.follow the progress of the sun through the heavens. .From the very first the stalks' of the plants began to bend, so that they, constantly presented themselves and their budding leaves towards the moon, they were the most fervid worshippers of Diana. ...,'.-

Professor' Tait .has been lecturing on thunderstorms with a view to showing the amount of energy involved in changes then produced. He proved that to evaporate a tenth/of an inch of water on a square foot of ground required a power equal to one hone. f«r half an hour, so that to condense onetenth of an inch of water on a square mile, would require' one million horses working for the same time. In. this way there is little diffionlty in; Understanding how it is that hurricanes and typhoons can be produced by: the amount of energy in the heat formed out of "thatemall quantity of water in condensing from.the 'Vaporous into the liquid form. Speaking of the three forms under which lightning is- usually' manifested—forked, aheet, ; and globular—Professor Tait said that forkedilightning was of the same kind that we obtained from 'an 1 electrical machine.- A brilliant flash of lightning lasts only. the. onemillionth part ,of -a, second.:" " Sheet', lightning is merely the blouds and,vapour in the atmosphere lighted by the forked kind. Of " globe"; lightning very little is at present known. Professor Tait expressed-It as "his that .'atmospherical eleotrioity was caused by Motion of the water r vapour moleaulea with those of the air. ' *"" "''""''''" "*""■'