SCIENCE OF WEATHER.

THERE are some scientific problems which are so closely connected

with daily life that every practical man thinks himself qualified to theorize on the subject, and the worst of it is, that just on these subjects even genuinely scientific men seem to be unhinged, and to lose that energetic dislike to baseless theory which they usually show. There are the currency fanatics, who are tempted by the tangible and visible simplicity of coin to think they can discover the law of com- mercial crises, and who go about puzzling foolish heads with the metaphysics of the pound sterling. There are the medical fanatics, 'who are tempted by the easy field of direct experiment which medi- cine holds out, to fancy they can reach the causes of ill-health, and 'who carry about tiny bottles of globules, which they administer

eagerly to themselves, or any one willing to share their delusions, whenever a fortunate headache or sore-throat confers an opportu- nity of tentative healing. And there are the many weather theorists, who are always imagining that they have some new aperfu as to the causes of change of weather, and who will tell you gravely they have "often noticed" laws of variation, about as true and important as that widely-sustained induction of London wayfarers, that whenever you want an omnibus in one direction, you are uniformly discomfited by a perfect string of the right omnibuses going in the opposite direction. If wild theories on these great scientific problems were confined to prat- ticalmen, who go out of their ordinary way to have a snatch at those pro- blems the insolubility of which they find the most annoying, only good would be done. Such men are not hurt by experiencing the difficulty of hitting on a true scientific hypothesis, and are, indeed, the better for learning that philosophy is a grander study than they have any notion of, and that a "plain man" cannot hope to fathom its deeper secrets by the rough application of the sort of inductive commoil sense which teaches him, as Lord Macaulay says, by an unconscious appli- cation of the Baconian method, that a cloudy day is the best for catching trout, or that minced pies are not the best permanent diet for an invalid. But the remarkable thing is' as we have said, not that plain men make these rude and impatient sallies into a region which they know nothing about, but that the chronic interest of the prac- tical world on these subjects seems to throw a charm even round scientific men. It has the effect of offering a into prize for a suc- cessful essay or invention ;—that is, it fosters nto life an unnatural number of strained unsuccessful efforts.

Take, for instance, the favourite problem of the weather. Every year brings into existence a crop of solutions from scientific as well as unscientific men, two of the most recent of which now lie before us. Yet these writers, even when most eminent, rarely begin by clearly defining what it is they wish explained. They would say, pro- bably, that it is the law of succession of wet and dry seasons in England that they search for,—but when we come to look at most of thew proposed solutions, we very soon find that it is implicitly as- sumed that there is nothing local, nothing limiting the hypothesis to England in the solutions proposed.

Thus the old lunar theory, still implicitly received by country folks, and held by many ladies as a fact of direct experience—the theory that weather is apt to change at the moon's quarters, clearly applies rather to the earth than to any particular spot on it. And all the various complicated forms of that theory, invented to supply its ap- parent failures—such as that a change from fine to wet may he ex- pected if the new quarter is entered on after midnight, and vice venal for a post-meridian change, are. liable to the same criticism. Again, a recent theorist, a Mr. Shepherd, C.E., who appears to prefer the planet Jupiter to the moon, has discovered the following elaborate law for the variations of our English weather, except so far as the principle is affected by comets —those invaluable disturb- ing causes which are always at hand to piece-out a lame weather hypothesis. He has invented4he following table :

METEOROLOGICAL ORDER.

Cycle.

Period of Jupiter 12 years

Constellations. Meteorological Order of the Cycle.

Series I III IV

VI

VII

vm lx XI Xu

Jupiter in

31 f I I 11 PP 'p

ID

PP

Leo Virgo Libra Scorpio Sagittarius and part of Capricornus Aquarius Pisces Aries Taurus Gemini Cancer Late spring, wet cold summer and autumn, changeable winter.

Early spring, fine summer and autumn, mild winter.

Cold spring, fine summer and autumn, cold winter.

Cold spring, fine summer and autumn, wet mild winter.

Early spring, wet warm summer, wet autumn, mild winter. Cold spring, wet summer, wet autumn, severe winter, great storms.

Cold spring, fine summer and autumn, severe winter.

Changeable spring, fine summer and autumn, changeable winter.

Cold spring, fine summer and autumn, changeable winter. Wet spring, wet summer and autumn, mild winter.

Early spring, fine summer and autumn, mild winter.

Cold spring, fine summer and autumn, cold *inter.

"The fine weather we almost always enjoy when Jupiter is in the constella- tions Gemini and Cancer. I am inclined to consider this phenomenon entirely due to the 'sweet influences of Pleiades and the bands of Orton.' "It is also very clear that the winters which precede and the springs which succeed the cold wet years bring us violent storms, like the November hurricane in 1859, and the late gales this year. "We have now traced the cycle of the climate of England, and in this cycle we experience all the changes and perturbations our climate is subject to."

This is very pretty, and fanciful. Mr. Shepherd is not quite with- out even higher authority. Only last year, no less a thinker than Sir John Herschel publicly intimated his suspicion that the periodic expansion in the sun's spots had some close connexion with the ex- traordinarily wet summer, and in his article on meteorology in the Encyclopedia Brilannica the same eminent authority has connected this periodic change in the sun's spots, which takes place in about twelve years, with the periodic, time of Jupiter's revolution round the sun (which is nearly the same in length), so that here we have an eminent aironomer half conceding the same very dubious prin- 6ple—that causes which affect equally, if not the whole earth, at least all places which, in the diurnal rotation, are brought into the same relative position towards the sun or the planet, are the principal influences which determine our local weather.

Yet, if this be so, how does it happen that the year 1860, which was abnormally wet in Europe, was abnormally dry in many other parts of the world ? If Mr. Shepherd be right in connecting this fact with the orbital position of Jupiter, or Sir John Herschel in connecting it with the large spots on the sun, it would scarcely have merely affected the local distribution of heat; or, if it could, the means by which these causes rob England to burn India remain as dark as before. Again, another recent meteorological theorist, Mr. Fullbrook, who, after examining, has rejected the theory that "planetary aspects" affect the weather, but will not disclose the six distinct cyclical causes which he has discovered in their place, tells us that he has dealt with the "published account of rainfalls during a long series of years," so as to generalize the connexion between them and the "celestial movements."

"The effects of which I speak, and which I am about to represent by a dotted curve, may be regarded as constituting a System of Cycles (six in number), each having a war and a DRY side, and a certain period or term of duration which being run through commences again. Hence they are constantly recurring through all time; and as they are of different lengths, every variety of combination will arise in successive years. When the war part of most or all of them coincide, or nearly so, in any year, the weather will prove extremely war; when the DRY portion of most of them occur together, the season will be very DRY; and when the war portion of some fall in with the DRY parts of others, the season, as regards moisture, will be of a medium character. . . .

They have been deduced, on strictly scientific principles, from the actual rainfall extending over a period of sixty years and upwards, and are, therefore, not merely theoretical. . . "On calculating backward, I find that remarkable coincidences of the war part of these Cycles occurred at the very time these extraordinary wet seasons happened in England, as recorded in history, two instances of which was the latter half of 1348 and that of 1703."

On looking at the course of this gentleman's pretty dotted curve, one is again puzzled to know what it exactly represents: if the rain- fall in all England, or special places in England, or in Great Britain, or Europe, or the world. Unfortunately, for the weather of the world—indeed for that of Europe—there can be no reliable materials at all; and yet how special "celestial movements" can be inferred as causes of such very partial phenomena as a series of rainfalls in one little spot of earth, when, for anything we know, an extension of observations all over the globe would entirely dissipate all sign of his supposed cycles of causes, it is difficult to imagine. Mr. Fullbrook has kindly given us a few prophecies which we can clearly test as to the present year :

"I will here notice some of the periods in the present year (1861) which are

likely to be of a rainy or unsettled character, hoping, before another year has elapsed, to materially improve this class of rules. The latter end of April or beginning of May. "The last few days of May. "The third week in June.

"A few days before and after the 20th of July. "Towards or about the middle of August. "The first two or three days. and about the middle of September. "About the second week in October."

Now, we cannot help asking to what regions these prophecies are meant to apply. While Yorkshire, Ireland, and Scotland have been deluged with incessant rain throughout the summer, Middlesex and the South have had an unusually bright and brilliant season, with a high and steady barometer; and as far as we can make out, there is no spot in England in which these prophecies have been verified. Do the six cycles, therefore, hold for the South or the North, or for the border land between the rain and sunshine ? It is satisfactory to find that while Mr. Fullbrook confidently predicts much rain for 1863, Mr. Shepherd says there is not the least doubt but it will be " a very fine and fruitful year !"

The truth seems pretty clear that local causes—especially causes changing the direction of the currents of the ocean and of the currents in the air—have quite as much, if not more, to do with weather, than any general causes affecting the whole earth. At all events, there is the unsolved general question whether or not the rain and heat on the earth, as a whole, is or is not nearly constant from year to year—whether weather is a phenomenon mainly of local distribution, or a phenomenon of terrestrial dimensions—and till this is solved there will probably be little basis for celestial h sotheses. In any case local causes must have very great influence.

atever be the true law of the weather, there will be plenty of local differences, and whenever it becomes possible to anticipate the heat of the summer, or to draw a map with lines indicating where unclouded weather may be expected, and where the rain streaks will fly along, we may suspect that it will be the joint work of hundreds of local meteorologists, rather than the simple fruit of any single principle. The great advantage to wedding tourists, travellers, invalids, and mankind in general, of predicting with any accuracy the alternations of sunshine and storm in all the different places on the surface of the earth, may indeed some day be within our grasp ; but as the matter at present stands, it seems very unlikely that it will ever be resolved into causes so simple as these mechanical ones which affect the seasons and the tides. There seems every reason to suspect that differences in level, in geological strata, and even in the distribution of wood and stream, may have as much to do with the result as sun, moon, or planets. Certainly the Gulf Stream and the Trade winds, and probably even Snowdon and Ben Lomond, Llanberris and Windermere, and Thames, Tees, or Teviot, affect the local weather more than the position of Jupiter or the spots on the sun.