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Show ' i Miscellany Sun Getting Restless. ' By GAEEETT P. SEEVISS. A bit of astronomical news, the importance im-portance of tvhieh will boconl'e more apparent as time goes on, is that the suu is nov entering upon another period pe-riod of maximum spottedness. Last year the surface of the sun was less disturbed than it had been for nearly a eentury before. At the beginning be-ginning of April this year a large spot broke out upon it, and as I write' now I can see, at the first glance with au opera glass (the eyes being protected by a. pair of eleetriciau 's black spectacles), spec-tacles), a huge ebon blot near the edge of the round disk, and it is only necessary neces-sary to turn a telescope upon that blot in order to behold a solar storm covering cov-ering a space far larger than the whole earth. But this spot is small compared with many which will be seen within' the next few years. Just as "the period of minimum, spottedness which culminated last year was extraordinarily quiet, so the maximum now coming on is likely like-ly to bo unusually euergetic. What will be the consequences to the earth l? There will be great magnetic storms, and probably munificent displays dis-plays of the aurora borealis, rolling its wonderful curtains in the polar skies. There is considerable reason for expecting ex-pecting that destructive tornadoes, cy-cloneH, cy-cloneH, typhoons and hurricanes will do unusually abundant during the next five or six years. Every atmospheric disturbance iu which electricity plays a conspicuous part is likely to be rnoro marked during dur-ing years of sunspot maximum. Some observations indicate that violent thunderstorms are more abundant at such times. It has been thought that a great "wave of heat" passing over the earth is characteristic of the beginning of a new sunspot period, like the present. This was the opinion of Pi-&7.7.1 Pi-&7.7.1 Smyth, the 8cotch astronomer, whose fascinating speculations about the origin and meaning of the Great Pyramid were regarded as too mystical by some of his scientific brethreu and lessened the weight of his authority on other subjects. For, . in science as in other human things, orthodoxy is a great asset. But, while there may be au increase of heat at. the beginning, yet the best opiniou of astronomers at present is that the earth, as a whole, gets a little less heMt from the sun during a maximum maxi-mum than during a minimum period ot spottedness. It is simply a matter of area; the spots cover hundreds of millions mil-lions of square miles of the sun's surface, sur-face, and since they are comparatively dark they cut off a proportional amount of radiation carrying heat to the earth. The loss to the earth amounts to a decrease of about one degree in the average height of the thermometer. To that extent, then, the sun is a variable star, with a period of a little over eleven years from one maximum to the next. But the periods are irregular not , only in length, but in intensity. |