396 



NA TURE 



[Sept. 6, 1877 



these numbers can now be taken. Enormous quantities of 

 shad have been bred from the egg and sent into the 

 waters in order to renew the supply ; many millions of 

 healthy young fish are thus annually added to the stock, 

 and fresh rivers are now being populated with shad. 



Another fish to which the commission has of late 

 directed its attention is the carp, Cypriniis carpio, and var. 

 It is a fish which is thou^jht to be eminently calculated 

 for the warmer waters of America, and especially suited 

 to the mill-ponds and sluggish rivers and ditches of the 

 south. Some most interesting information is given about 

 the carp and its numerous varieties, but it is too detailed 

 for quotation. Another noteworthy feature of American 

 fish-culture is the transport, in " an aquarium car," to the 

 coast and inland waters of California, of various fishes 

 and crustaceans of North America, in order to test the 

 question of whether they could be acclimatised in the 

 warmer latitudes of the Pacific. The first experiment 

 failed through an accident on the railway, but on June 

 12, 1874, the car arrived safely with its interesting freight. 

 Out of a lot of 150 lobsters which were placed in the 

 aquarium car, only four, however, were left alive on reach- 

 ing San Francisi o B.iy, and these were put into the sea 

 at Oakland Wharf, nine days after they had been taken 

 from the Atlantic Ocean. It is thought probable that the 

 four specimens did not ultimately live, but as two of the 

 four were big with spawn it is probable the eggs would 

 come to maturity, as the death of the parent does not kill 

 the spawn. Lobster eggs, unlike fish ova, are fructified 

 before they leave the body of the animal. 



An interesting account is given in the present volume 

 of the American oyster fisheries. 



LETTERS TO THE EDITOR 



[The Editor does not hold himsei/ responsible for opinions expressed 

 by his correspondents. Neither can he undertake to return^ 

 or to correipond with the writers of, rejected matmscripts. 

 No notice ts taken of anonymous cornniunuations. 



The Editor urgently requests correspondents to keep their letters as 

 short as possible. The pressure on his space is so great that it 

 is impossible otherwise to ensure the app arance even of com- 

 viunications containing interesting and novel facts.'[ 



Indian Rainfall and Sun-spots 



Since my last communication to you on the above subject I 

 have had some correspondence with Mr. Hill, the meteorological 

 reporter to the North-West Provinces, in the course of which he 

 has given me a more definite account of the results of his inves- 

 tigations. The outcome of our joint researches may be broadly 

 stated as follows : — In years of maximum sun-spot the summer 

 rainlall is ahojie and the winter rainfall beloiu the average, while 

 in years of minimum sun-spot the reverse conditions hold, viz., 

 the summer rainfall is beiotv and the winter rainfall aboiie the 

 average. 



Though the preceding hypothesis can only be considered at 

 present in the light of a probability, it is considerably strength- 

 ened by the fact that, unknown to each other, Mr. Hill and 

 myself have each taken it as the basis of our separate, and until 

 recently, independent lines of inquiry. Mr. IIill has already 

 sent in a short report to Government of the results of hts own 

 investigations, which he roughly states in the following words : — 

 *' I have examined the rainfall of Benares, Allihabad, Agra, 

 Bareilly, Roorkee, Dehra, Mussoorie, and Naini Tal, since 1861, 

 and I find that on the average the total annual rainfall of the 

 maximum sun-spot years 1S61, 1S69, 1870, and 1S71, is about 

 14 per cent, above the average for the whole period, and that of 

 the minimum group 1866, 1867, and 1868, about 4 per cent, 

 below it. On the other hand, when only the win/er rainfall is 

 considered, the defect in maximum sun-spot years is about 21 

 per cent, of the average winter tall, and the excess in minimum 

 sun-spot years is above 20 per cent." Unfortunately no furihtr 

 data appear to be available in the North-West Provinci-s, as 

 during the mutiny decade, 1851-18(10, no rc>,ister was ke('t, and 

 belore the mutiny the Schlagintweits took away to Germany most 

 of the old rainfall records. The results, however, as far as they 



go, are in complete accordance with those I have obtained from 

 a similar comparison of some of the rainfalls in Bengal. 



The chief obstacles in the way of making a thoroughly 

 complete and exhaustive comparison of the rainfalls throuLihout 

 Northern India are (1) the paucity of registers, and (2) the 

 limited periods over which they extend. In the single case of 

 Calcutta the latter objeciion does not apply, since by dint of 

 some trouble I have succeeded in obtaining the monthly as well 

 as the annual falls for a period of forty years, from 1S33 to 1876 

 inclusive. As this comprises four complete sun-spot cycles, the 

 results are extremely valuable, especially as they tend to exhibit 

 what Prof. Balfour Stewart considers to be the true test of a 

 physical cycle, viz., its repetition. 



I here append a comparison of the rainfall of Calcutta, for 

 the months of January, February, and March, arranged in four 

 groups of minimum and maximum sun-spot years, together with 

 the years immediately preceding and following them (except in 

 the case of the former, where the rise after the minimum is often 

 very rapid). 



1842) 



1S43 



1844! 



1854 



1855 



1875 

 1876 

 1877 



Total of all j 

 the groups, j 



Total of each 

 group. 



inches. 



7 -So 

 7-29 



14 -60 



4258 



1836) 



1837 [ 

 1838) 

 18471 

 1848 

 1849 > 



Total of each 

 group. 



3-54 



1870 



6-42 



976 



Total of all ] 

 the groups. \ 



26^40 



In addition to this it may be noted that the total fall during 

 the same three months of the four absolute minimum sun-spot 

 years 1S43, 1856, 1867, and 1877 (probable minimum) is I5'98 

 inches, while that of the four absolute maximum sun-spot years, 

 1837, 1848, i860, and 1870, reaches only the insignificant 

 amount of 2 48 inches. Similar results are obtained if the 

 month of April and the months of November and December of 

 the preceding years are respectively included, thus evidently 

 showing that the relation is one connected with the seasonal 

 distribution of the rainfall and not merely a coincidence, resulting 

 from having taken the rainfalls of special months. 



If we treat the rainfall ot Dehra, from 1861 to 1S77, in a 

 somewhat similar manner, by taking the rainlalls of January, 

 February, and the previous December, and consider 1861, 1862, 

 and 1863 to approximately represent a maximum group, the 

 results are as follows: — 



I think an examination of the preceding comparisons of the 

 winter rainfalls of Dehra and Calcutta (rough though they 

 undoubtedly are) discloses distinct evidence of repetition in 



