westerly winds were slightly more common (as compared with other winds) when sun-spots were numerous than when they were few.
Mr. Meldrum, of Mauritius, has made a series of statistical inquiries into the records of cyclones which have traversed the Indian Ocean between the equator and 34 degrees south latitude, in each year from 1856 to 1877, noting the total distances traversed by each, the sums of their radii and areas, their duration in days, the sums of their total areas, and their relative areas. His researches, be it marked in passing, are of extreme interest and value, whether the suggested connection between sun-spots and cyclones (in the region specified) be eventually found to be a real one or not. The following are his results, as described in Nature by a writer who manifestly favours very strongly the doctrine that an intimate association exists between solar maculation (or spottiness) and terrestrial meteorological phenomena:—
“The period embraces two complete, or all but complete, sun-spot periods, the former beginning with 1856 and ending in 1867, and the latter extending from 1867 to about the present time [1877]. The broad result is that the number of cyclones, the length and duration of their courses, and the extent of the earth’s surface covered by them all, reach the maximum in each sun-spot period during the years of maximum maculation, and fall to the minimum during the years of minimum maculation. The peculiar value of these results lies in the fact that the portion of the earth’s surface over which this investigation extends, is, from its geographical position and what may be termed its meteorological homogeneity, singularly well fitted to bring out prominently any connection that may exist between the condition of the sun’s surface and atmospheric phenomena.”
The writer proceeds to describe an instance in which Mr. Meldrum predicted future meteorological phenomena, though without specifying the exact extent to which Mr. Meldrum’s anticipations were fulfilled or the reverse. “A drought commenced in Mauritius early in November,” he says, “and Mr. Meldrum ventured (on December 21) to express publicly his opinion that probably the drought would not break up till towards the end of January, and that it might last till the middle of February, adding that up to these dates the rainfall of the island would probably not exceed 50 per cent. of the mean fall. This opinion was an inference grounded on past observations, which show that former droughts have lasted from about three to three and a half months, and that these droughts have occurred in the years of minimum sun-spots, or, at all events, in years when the spots were far below the average, such as 1842, 1843, 1855, 1856, 1864, 1866, and 1867, and that now we are near the minimum epoch of sun-spots. It was further stated that the probability of rains being brought earlier by a cyclone was but slight, seeing that the season for cyclones is not till February or March, and that no cyclone whatever visited Mauritius during 1853–56 and 1864–67, the years of minimum sun-spots. From the immense practical importance of this application of the connection between sun-spots and weather to the prediction of the character of the weather of the ensuing season, we shall look forward with the liveliest interest to a detailed statement of the weather which actually occurred in that part of the Indian Ocean from November to March last [1876].”
It was natural that the great Indian famine, occurring at a time when sun-spots were nearly at a minimum, should by some be directly associated with a deficiency of sun-spots. In this country, indeed, we have had little reason, during the last two or three years of few sun-spots, to consider that drought is one of the special consequences to be attributed to deficient solar maculation. But in India it may be different, or at least it may be different in Madras, for it has been satisfactorily proved that in some parts of India the rainfall increases in inverse, not in direct proportion, to the extent of solar maculation. Dr. Hunter has shown to the satisfaction of many that at Madras there is “a cycle of rainfall corresponding with the period of solar maculation.” But Mr. E. D. Archibald, who is also thoroughly satisfied that the sun-spots affect the weather, remarks that Dr. Hunter has been somewhat hasty in arguing that the same conditions apply throughout the whole of Southern India. “This hasty generalization from the results of one station situated in a vast continent, the rainfall of which varies completely, both in amount and the season in which it falls, according to locality, has been strongly contested by Mr. Blanford, the Government Meteorologist, who, in making a careful comparison of the rainfalls of seven stations, three of which (Madras, Bangalore, and Mysore) are in Southern India, the others being Bombay, Najpore, Jubbulpore, and Calcutta, finds that, with the exception of Najpore in Central India, which shows some slight approach to the same cyclical variation which is so distinctly marked in the Madras registers, the rest of the stations form complete exceptions to the rule adduced for Madras, in many of them the hypothetical order of relation being reversed. Mr. Blanford, however, shows that, underlying the above irregularities, a certain cyclical variation exists on the average at all the stations, the amount, nevertheless, being so insignificant (not more than 9 per cent. of the total falls) that it could not be considered of sufficient magnitude to become a direct factor in the production of famine. It thus appears that the cycle of rainfall which is considered to be the most important element in causing periodic famines has only been proved satisfactorily for the town of Madras. It may perhaps hold for the Carnatic and Northern Siccars, the country immediately surrounding Madras, though perhaps, owing to the want of rainfall registers in these districts, evidence with regard to this part is still wanting.” On this Mr. Archibald proceeds to remark that, though Dr. Hunter has been only partially successful, the value of his able pamphlet is not diminished in any way, “an indirect effect of which has been to stimulate meteorological inquiry and research in the same direction throughout India. The meteorology of this country (India), from its peculiar and tropical position, is in such complete unison with any changes that may arise from oscillations in the amount of solar radiation, and their effects upon the velocity and direction of the vapour-bearing winds, that a careful study of it cannot fail to discover meteorological periodicities in close connection with corresponding periods of solar disturbance.” So, indeed, it would seem.
The hope that famines may be abated, or, at least, some of their most grievous consequences forestalled by means of solar observatories, does not appear very clearly made out. Rather it would seem that the proper thing to do is to investigate the meteorological records of different Indian regions, and consider the resulting evidence of cyclic changes without any special reference to sun-spots; for if sun-spots may cause drought in one place, heavy rainfall in another, winds here and calms there, it seems conceivable that the effects of sun-spots may differ at different times, as they manifestly do in different places.
Let us turn, however, from famines to shipwrecks. Perhaps, if we admit that cyclones are more numerous, and blow more fiercely, and range more widely, even though it be over one large oceanic region only, in the sun-spot seasons than at other times, we may be assured, without further research, that shipwrecks will, on the whole, be more numerous near the time of sun-spot maxima than near the time of sun-spot minima.
The idea that this may be so was vaguely shadowed forth in a poem of many stanzas, called “The Meteorology of the Future: a Vision,” which appeared in Nature for July 5, 1877. I do not profess to understand precisely what the object of this poem may have been—I mean, whether it is intended to support or not the theory that sun-spots influence the weather. Several stanzas are very humorous, but the object of the humour is not manifest. The part referred to above is as follows:—Poor Jack lies at the bottom of the sea in 1881, and is asked in a spiritual way various questions as to the cause of his thus coming to grief. This he attributed to the rottenness of the ship in which he sailed, to the jobbery of the inspector, to the failure of the system of weather telegraphing, and so forth. But, says the questioner, there was one
“In fame to none will yield,
He led the band who reaped renown
On India’s famine field.
“Was he the man to see thee die?
Thou wilt not tax him—come?
The dead man groaned—‘I met my death Through a sun-spot maximum.’”
The first
