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Plimsoll’s endeavours), which should have been broken up; whereas in times of trade depression the ships actually afloat are likely to be, on the average, of a better class. So also, when, for some special reason, passenger traffic at sea is abnormally increased. I merely mention these as illustrative cases of causes not (probably) dependent on sun-spots, which may (not improbably) have affected the results examined by Mr. Jeula. I think it possible that those results, if presented for each year, would have indicated the operation of such causes, naturally masked when sets of four years, four years, and three years are taken instead of single years.

      I imagine that considerations such as these will have to be taken into account and disposed of before it will be unhesitatingly admitted that sun-spots have any great effect in increasing the number of shipwrecks.

      The advocates of the doctrine of sun-spot influence—or, perhaps it would be more correct to say, the advocates of the endowment of sun-spot research—think differently on these and other points. Each one of the somewhat doubtful relations discussed above is constantly referred to by them as a demonstrated fact, and a demonstrative proof of the theory they advocate. For instance, Mr. Lockyer, in referring to Meldrum’s statistical researches into the frequency of cyclones, does not hesitate to assert that according to these researches “the whole question of cyclones is merely a question of solar activity, and that if we wrote down in one column the number of cyclones in any given year, and in another column the number of sun-spots in any given year, there will be a strict relation between them—many sun-spots, many hurricanes; few sun-spots, few hurricanes.” ... And again, “Mr. Meldrum has since found” (not merely “has since found reason to believe,” but definitely, “has since found”) “that what is true of the storms which devastate the Indian Ocean is true of the storms which devastate the West Indies; and on referring to the storms of the Indian Ocean, Mr. Meldrum points out that at those years where we have been quietly mapping the sun-spot maxima, the harbours were filled with wrecks, and vessels coming in disabled from every part of the Indian Ocean.” Again, Mr. Balfour Stewart accepts Mr. Jeula’s statistics confidently as demonstrating that there are most shipwrecks during periods of maximum solar activity. Nor are the advocates of the new method of prediction at all doubtful as to the value of these relations in affording the basis of a system of prediction. They do not tell us precisely how we are to profit by the fact, if fact it is, that cyclones and shipwrecks mark the time of maximum solar maculation, and droughts and famine the time of minimum. “If we can manage to get at these things,” says Mr. Lockyer, “the power of prediction, that power which would be the most useful one in meteorology, if we could only get at it, would be within our grasp.” And Mr. Balfour Stewart, in a letter to the Times, says, “If we are on the track of a discovery which will in time enable us to foretell the cycle of droughts, public opinion should demand that the investigation be prosecuted with redoubled vigour and under better conditions. If forewarned be forearmed, then such research will ultimately conduce to the saving of life both at times of maximum and minimum sun-spot frequency.”

      If these hopes are really justified by the facts of the case, it would be well that the matter should be as quickly as possible put to the test. No one would be so heartless, I think, as to reject, through an excess of scientific caution, a scheme which might issue in the saving of many lives from famine or from shipwreck. And on the other hand, no one, I think, would believe so ill of his fellow-men as to suppose for one moment that advantage could be taken of the sympathies which have been aroused by the Indian famine, or which may from time to time be excited by the record of great disasters by sea and land, to advocate bottomless schemes merely for purposes of personal advancement. We must now, perforce, believe that those who advocate the erection of new observatories and laboratories for studying the physics of the sun, have the most thorough faith in the scheme which they proffer to save our Indian population from famine and our seamen from shipwreck.

      But they, on the other hand, should now also believe that those who have described the scheme as entirely hopeless, do really so regard it. If we exonerate them from the charge of responding to an appeal for food by offering spectroscopes, they in turn should exonerate us from the charge of denying spectroscopes to the starving millions of India though knowing well that the spectroscopic track leads straight to safety.

      I must acknowledge I cannot for my own part see even that small modicum of hope in the course suggested which would suffice to justify its being followed. In my opinion, one ounce of rice would be worth more (simply because it would be worth something) than ten thousand tons of spectroscopes. For what, in the first place, has been shown as to the connection between meteorological phenomena and sun-spots? Supposing we grant, and it is granting a great deal, that all the cycles referred to have been made out. They one and all affect averages only. The most marked among them can so little be trusted in detail that while the maximum of sun-spots agrees in the main with an excess or defect of rain or wind, or of special rains with special winds, or the like, the actual year of maximum may present the exact reverse.

      Of what use can it be to know, for instance, that the three years of least solar maculation will probably give a rainfall less than that for the preceding or following three years, if the middle year of the three, when the spots are most numerous of all, may haply show plenteous rainfall? Or it may be the first of the three, or the last, which is thus well supplied, while a defect in the other two, or in one of the others, brings the total triennial rainfall below the average. What provision could possibly be made under such circumstances to meet a contingency which may occur in any one of three years? or, at least, what provision could be made which would prove nearly so effective as an arrangement which could readily be made for keeping sufficient Government stores at suitable stations (that is, never allowing such stores to fall at the critical season in each year below a certain minimum), and sending early telegraphic information of unfavourable weather? Does any one suppose that the solar rice-grains are better worth watching for such a purpose than the terrestrial rice-grains, or that it is not well within the resources of modern science and modern means of communication and transport, to make sufficient preparation each year for a calamity always possible in India? And be it noticed that if, on the one hand, believers in solar safety from famine may urge that, in thus objecting to their scheme, I am opposing what might, in some year of great famine and small sun-spots, save the lives of a greater number than would be saved by any system of terrestrial watchfulness, I would point out, on the other, that the solar scheme, if it means anything at all, means special watchfulness at the minimum sun-spot season, and general confidence (so far as famine is concerned) at the season of maximum solar maculation; and that while as yet nothing has been really proved about the connection between sun-spots and famine, such confidence might prove to be a very dangerous mistake.

      Supposing even it were not only proved that sun-spots exert such and such effects, but that this knowledge can avail to help us to measures of special precaution, how is the study of the sun going to advance our knowledge? In passing, let it be remarked that already an enormous number of workers are engaged in studying the sun in every part of the world. The sun is watched on every fine day, in every quarter of the earth, with the telescope, analyzed with the spectroscope, his prominences counted and measured, his surface photographed, and so forth. What more ought to be or could be done? But that is not the main point. If more could be done, what could be added to our knowledge which would avail in the way of prediction? “At present,” says Mr. Balfour Stewart, “the problem has not been pursued on a sufficiently large scale or in a sufficient number of places. If the attack is to be continued, the skirmishers should give way to heavy guns, and these should be brought to bear without delay now that the point of attack is known.” In other words, now that we know, according to the advocates of these views, that meteorological phenomena follow roughly the great solar-spot period, we should prosecute the attack in this direction, in order to find out—what? Minor periods, perhaps, with which meteorological phenomena may still more roughly synchronize. Other such periods are already known with which meteorological phenomena have never yet been associated. New details of the sun’s surface? No one has yet pretended that any of the details already known, except the spots, affect terrestrial weather, and the idea that peculiarities so minute as hitherto to have escaped detection can do so, is as absurd, on the face of it, as the supposition that minute details in the structure of a burning coal, such details as could only be detected by close scrutiny, can affect the general quality and effects

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