NA TURE 



{June 28, 1877 



This table is of peculiar value with regard to the many 

 questions at present under discussion in connection with 

 sun- spots. 



Sun-Spots and the Prediction of the Weather 

 OF the Coming Season at Mauritius.— In the 

 JSIonthly Notices, new series, No. i, of the Meteorological 

 Society of Mauritius (December 21, 1876), Mr. Meldrum 

 gives a clear and interesting summary of his researches 

 into the relations of sun-spots to several atmospheric 

 phenomena. A valuable table appears on p. 14 setting 

 forth the number of cyclones which have occurred in the 

 Indian Ocean between the equator and 34° lat. S. each 

 year from 1856 to 1875, the total distances traversed by 

 these cyclones, the sums of their radii and areas, their 

 duration in days, the sums of their total areas, and their 

 relative areas. The well-known thoroughness with which 

 the Meteorological Society of Mauritius has worked at 

 the storms of the Indian Ocean ensures that the subject 

 has been exhaustively treated. The period embraces two 

 cojTiplete, or all but complete, sun-spot periods, the former 

 beginning with 1856 and ending 1867, and the latter 

 extending from 1867 to about the present time. 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 posi- 

 tion and what may be termed its meteorological homo- 

 geneity, singularly well fitted to bring out prominently 

 any connection that may exist between the condition 

 of the sun's surface and atmospheric phenomena. A 

 drought commenced in Mauritius early in November, 

 1S76, and when the paper was read on December 21, Mr. 

 Meldrum ventured 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 50percent. 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 what- 

 ever visited Mauritius during 1853-56 and 1864-67, the 

 years of minimum sun-spots. From the immense practi- 

 cal importance of this application of the connection be- 

 tween sun-spots and weather to the prediction of the 

 character of the weather of the coming season, we shall 

 look forward with the liveliest interest to a detailed state- 

 ment of the weather which actually occurred in that part 

 of the Indian Ocean from November to March last. 



Meteorology in South Australia.— The publi- 

 cation of the meteorological observations made in this 

 colony, which required to be discontinued in 1870 owing 

 to the heavy pressure of ofhcial duties devolving on Mr. 

 Charles Todd in connection with the construction and 

 organisation of the Overland Telegraph, was resumed in 

 an extended form in January, 1876, and we have now 

 before us the first nine monthly issues, which bring the 

 publication down to the end of September last. The 

 reports detail, with some care, the conditions under which 

 the observations are taken, the three or six daily obser- 

 vations made, and full resioiih of the monthly results. 

 An extremely valuable part of the reports is the monthly 

 table of the rainfall at upwards of eighty stations, as 

 observed by the officers of the postal and telegraph 

 departments, and a number of volunteer observers who 

 have co-operated with Mr. Todd in observing the rainfall 

 for many years. The stations are arranged in geographical 

 order from north to south, commencing with Port Dar- 

 win on the north coast, and along with the monthly 

 amounts there are also given the averages of the month 

 at all those places at which at least seven years' obser- 

 vations have been made. Among the many points of 

 interest offered by these tables are the torrential rains of 

 the north coast in the first three months of the year, fre- 

 quently rising to from ten to sixteen inches in the month, 

 their rapid diminution on advancing inland to Barrow's 

 Creek or Alice Springs, and the great diminution in 

 April, and the rainless, or all but rainless character of 

 the northern region from June to September, when the 

 prevailing winds of Australia become decidedly con- 

 tinental, or blow from the interior seawards. Since it 

 would be impossible to over-estimate the importance ot 

 barometrical and thermometrical observations from this 

 extended network of stations in South Australia, we very 

 earnestly hope that the Colony will soon take steps to 

 obtain these observations and publish them in the interest 

 of meteorology. 



Rainfall Observations in the East of France 

 from 1763 to 1870. — In the Bulletin Hebdomadaire oi 

 the Scientific Association of France, of the loth instant. 

 Prof. Raulin gives an interesting historical account of all 

 the rainfall observations made during these 108 years 

 anywhere in that section of France which is marked off 

 by lines joining Givet on the Meuse, Lauterbourg on the 

 Rhine, Belley near the Rhon, and Decize on the Loire, 

 and which thus comprehends seven well-marked regions, 

 VIZ., the plain of Alsace, the chain of the Vosges, the pla- 

 teaux of Lorraine and Bourgogne, the plains of Cham- 

 pagne and Bresse, and finally the chain of the Jura 

 mountains. During the past three years Prof Raulin has 

 been engaged collecting all available materials for a mo- 

 nograph on the rainfall of this part of Europe, which, 

 judging from his great monographs of the rainfall of other 

 sections of France and of the rainfall of Algeria, will 

 doubtless take its place as a permanent contribution of 

 very high value to meteorological science. 



