i68 



NATURE 



[Dec. 1 8, 1879 



The above table showed that the rainfall and sun-spots were, 

 with a single exception, both below or above their respective 

 means in the same years, and it would be seen that as the one 

 increased or decreased, so did the other. 



The separate results for Europe, America, India, and the 

 stations in the Southern Hemisphere were similar. Those for 

 Europe, for example, derived from observations taken at ninety- 

 nine stations, were as follows : 



Similar results were obtained by taking the sun-spot cycles 

 separately. Those for the cycle 1856-67, were as follows :— 



The observations at many single stations, when treated by 

 themselves, gave similar results. Those for Edinburgh and 

 Bombay from 1824 to 1867, and for the Cape of Good Hope 

 from 1843 to 1867, were as follows : — 



It had also been found that the levels of the principal rivers 

 of Europe, and those of the great American lakes, had on the 

 whole varied with the amount of sun-spots. 



Such were a few of the results for the four sun-spot cycles 

 from 1824 to 1867. Now it was important to remark that the 

 evidence had increased as the rainfall observations had increased. 

 Hence, with the large number of observing stations now spread 

 over the world, it was inferred that a few more sun-spot cycles 

 would settle the question of a corresponding rainfall cycle, if it 

 was not settled already. 



Another way of testing the matter in a comparatively short 

 time was to compare, as far as possible, the daily, weekly, or 



monthly rainfall of the globe with the sun's-spotted area ; for 

 the amount of sun-spots varied much in the course of a year. 



The results for the sun-spot cycle which commenced in 1S67, 

 and which probably was now closing, were not yet fully known, 

 but there was reason to believe that they would be similar to 

 those obtained for former cycles. It could already be stated that 

 a mean of a large number of observations made in all parts of 

 the world showed that the rainfall in the years 1S70-72 had been 

 greater than that in the years 1865-67, and judging from the 

 severe droughts that had occurred in India, China, japan, 

 Australia, South Africa, South America, &c, nnce 1876," it was 

 not improbable that the rainfall of the last three years had been 

 less than that of the years 1870-72. In 1877 and 1878 the Nile, 

 at Cairo, was lower than it had been for many years, showing 

 that in the regions drained by it there had been a deficiency of 

 rain. There had also of late years been a gradual decrease in 

 the depth of water in the upper portions of the Amazon, so that 

 navigation had sometimes been impeded, and this was supposed 

 to be due to a general diminution of rainfall in the interior of 

 South America. Moreover, various parts of the United States 

 had lately been suffering from drought. 



It would appear, then, that the circumstance that the rainfall 

 of Paris had for a long period been greater in the years of 

 maximum than of minimum sun-spots, was not a mere coincid- 

 ence, but the result of a general law, and a similar remark 

 applied to the rainfalls of many other public observatories. 



There were, as might be expected in the case of so fickle an 

 element as the rain, great local exceptions to the general law, 

 though not greater or more frequent than exceptions to the 

 general laws of other cycles ; but, as far as had yet been ascer- 

 tained, the rainfall of the globe varied directly as the sun-spots 

 varied, the deficiency at some places in the maximum years 

 being more than made up by the excess at others, and the excess 

 in the minimum years reduced by a proportionately greater 

 deficiency elsewhere. 



Great fluctuations occurred near the epochs of maximum and 

 minimum, but at a large majority of stations the rainfall in 

 the three years of most sun-spots was almost invariably greater 

 than that in the three years of fewest sun-spots. 



The general rainfall cycle for the whole globe might be 

 conceived to be made up of a number of local cycles differing 

 more or less among themselves and from the general cycle, 

 according to local conditions, and in some places the general 

 cycle might be reversed. 



From this point of view, it was possible that, although the 

 recent rainy weather in Western Europe, at a time when there 

 were few or no sun-spots, was a deviation from the general law, 

 yet it was not an exception to the particular modification of it 

 which prevailed in that part of the world. As a matter of fact, 

 the rainfall of Western Europe was considerably above the 

 average in 1844-45, 1845-55, anc ' 1S66-67, that is at intervals the 

 mean length of which was eleven years, and at times when there 

 were few sun-spots But Western Europe was only a small part 

 of the earth's surface ; and from such a deviation, it could not 

 be inferred that the rainfall, generally, was above the average in 

 the minimum years. 



In Mauritius there had been continuous observations only 

 since 1852. Since that time the rainfall had on the whole been 

 considerably less in the minimum than in the maximum years, 

 but it would take some time to eliminate the effects of local 



SCIENTIFIC SERIALS 

 Zeitschri/t fur wissenschaftliche Zoohgie, 33 Ed., I and 2 

 Heft, October 29, with seventeen plates. — F. E. Schulze, re- 

 searches upon the structure and the development of the sponges ; 

 eighth notice. — On the genus Hircinia of Nardo, and on 

 Obgoceras, a new genus, Plates I to 4. The genus of Nardo 

 equals Stematumenia of Bowerbank ; Sarcotragus, O. Schmidt ; 

 Filifera, Lieberkiihn ; and Polytherses of Duchassaing and 

 Michelotti. The structure of the filaments— alga: of some 

 authors— is fully discussed. The new genus Oligoceras is 

 established for a new species (collective) from Lesina, which, 

 though a fibrous sponge, is almost destitute of fibrous material. 

 — Prof. E. Selenka, on the germ lamelloeand the arrangement of 

 the organs in the Echinidx, Plates 5 and 7.— Prof. A. Weismann, 

 Contributions to the natural history of the Daphnidje, No. 6 

 and 7, with Plates 8 to 13. — Prof. P. Langerhans, on the worm 

 fauna of Madeira, with Plates 14 to 17. 



