April 7, 1892] 



NATURE 



545 



magnetic observatories. The plates which accompany the 

 text show plans of heating and ventilating the Pavlovsk and 

 Potsdam Observatories, the cellar and ground plans of the latter, 

 and details of instruments used in other Observatories, In the 

 second and third appendices will be found all the magnetic and 

 meteorological observations made in the years 1890 and 1883-87 

 respectively : these are brought together in a way that will 

 be found most convenient for reference, while several plates 

 showing the mean diurnal variations of some of the magnetic 

 elements have been added. All the above-mentioned observa- 

 tions have been reduced in the usual way, and the results 

 obtained are here tabulated. 



On Thursday and Friday, last week, a tornado passed over 

 the North-Western States of America and caused enormous 

 damage and great loss of life, in some cases whole towns being 

 devastated. It is said to have been the most far-reaching and 

 destructive storm ever known to have occurred in these regions. 

 Texas, Kansas, Missouri, Iowa, and Nebraska suffered most. 



In the Annual Report for 1892 of the Berlin branch of the 

 German Meteorological Society, Prof. G. Hellmann gives an ac- 

 count of his continued experiments on the effects of exposure on 

 rainfall records, and on the determination of the distance apart 

 that rain-gauges should be erected in order to obtain an accu- 

 rate account of the rainfall of any district. Simple as the 

 question appears, the experiments, which have been carried on 

 for seven years, have not sufficed to give a definite answer. 

 Very considerable differences are found in the amounts recorded 

 at stations comparatively close to each other. This result is 

 partly owing to the effect of wind, especially in the case of snow 

 The following are the most important conclusions derived from 

 the experiments :— (i) The more a rain-gauge is exposed to the 

 wind, under otherwise similar circumstances, the less rainfall it 

 records, and the higher a gauge is placed above the ground, the 

 less rain it catches, as the disturbing influence of the wind is 

 greater than on the surface of the ground. But if properly 

 protected from the wind, a gauge will give useful results 

 in an elevated position. The usual instructions to erect the 

 gauge as openly as possible are therefore incorrect. (2) Even in 

 a flat country, differences of 5 per cent, occur in different 

 months, at stations a quarter of a mile apart ; in stormy weather 

 especially during thunderstorms, the difference may amount to 

 100 per cent. The amounts recorded at neighbouring stations 

 agree better together in spring and autumn, and also in re- 

 latively wet years. Further experiments are needed, if pos- 

 sible by means of anemometers erected at the same level as the 

 rain-gauges, to determine more accurately the effect of wind on 

 both rainfall and snow. 



In connection with the celebration of the fourth centenary of 

 the discovery of America by Columbus, the Italian Botanical 

 Society invites the attendance of botanists of all countries at a 

 Botanical International Congress, to be held at Genoa, from the 

 4th to the nth of September. In addition to the meeting for 

 scientific purposes, there will be excursions on the shores of the 

 Mediterranean and in the Maritime Alps ; and during the same 

 time will also take place the inauguration of the new Botanical 

 Institute built and presented to the University of Genoa by the 

 munificence of Mr. Thomas Hanbury, of La Mortola, and the 

 opening of an Exhibition of Horticulture. All communications 

 should be addressed to Prof. Penzig, of the University of Genoa. 



Harvard University is indebted to the munificence of 

 Prof. George L. Goodale, the Director of the Botanic Garden 

 at Cambridge, Mass., for a remarkable development of the 

 botanical establishment of the University during the last ten 

 years. It has acquired a large fire-proof Museum, to contain not 

 only its collections, but its lecture-rooms and laboratories ; has 

 NO. II 7 1, VOL. 45] 



added greatly to its collections and its library ; and has also 

 obtained larger permanent funds for its support. 



In a report on the Great Skua in Shetland during the season 

 of 1891, printed in the new number (the second) of the Annals 

 of Scottish Natural History, Mr. W. E. Clarke says" that the 

 attention which was called to the persecution of the Great Skua, 

 at the close of the disastrous breeding season of 1890, was the 

 means of doing much good. It aroused and secured the interest 

 and influence of ornithologists and others on behalf of the 

 bird's future welfare and its preservation as an indigenous 

 British species. He notes that the number of Skuas resorting 

 to Foula annually during the summer may be estimated at not 

 less than 120 individuals. Of these, two-thirds are to be 

 reckoned as breeding birds. 



Messrs, Macmillan and Co. have issued a second edition 

 of Mr. A. R. Wallace's well-known " Island Life, or the 

 Phenomena and Causes of Insular Faunas and Floras." The 

 work has been carefully revised throughout, and, owing to the 

 great increase to our knowledge of the natural history of some 

 of the islands during the last twelve years, considerable additions 

 and alterations have been required. 



The paper on the opium question, recently read by Mr. G. 

 H. M. Batten before the Society of Arts, is printed in the 

 current number of the Society's journal. It is followed by a 

 report of the animated discussion to which it gave rise, and by 

 statements which would have been submitted to the meeting by 

 various gentlemen if there had been time. Mr. Batten cites the 

 opinion of a number of " independent persons of high character 

 and reputation," to the effect that "the daily use of opium in 

 moderation is not only harmless but of positive benefit, and fre- 

 quently even a necessity of life " ; and that *' this moderate use 

 is the rule, and excess the exception." Persons who have 

 arrived at an opposite conclusion have had an experience, he 

 thinks, almost entirely confined to towns and the sea coast. 

 " They knew little or nothing of the millions of the healthy, in- 

 dustrious population in the interior of the country to whom the 

 use of opium is as common, as moderate, and as beneficial as that 

 of beer is to the people of England." 



A WRITER in Nature Notes, calling attention to " the iniquity 

 of rooting up wild flowers to sell them to English dealers," says 

 he could name a district in the Basses Pyrenees, where not a 

 single wild daffodil is now to be found. The flower was once 

 abundant there, but an English resident chose to bargain with a 

 well-known dealer, to furnish him with roots ; and this has been 

 attended by grave injustice to France. 



Mr. G. C. Green records in Nature Notes for April a curious 

 reminiscence with regard to a pair of jackdaws kept by him at 

 Modbury Vicarage, South Devon, about twenty years ago. 

 They had been taken from the nest, and during the first summer 

 their wings were slightly clipped. After this their wings were 

 allowed to grow, and they lived at full liberty in the garden. 

 They were perfectly tame, and would come at call and feed out 

 of the hand, would come into the house, and in the morning 

 knock at the windows to ask for some breakfast. In the spring 

 they used to fly away and join their wild companions, make their 

 nests, and rear a family ; but when this was over they came 

 back to the garden again, fed from the hand, and were as tame 

 as ever. But the curious thing was, that after one or two seasons 

 they brought another jackdaw with them, presumably the young 

 of one of them, which was just as tame as themselves, although 

 nothing had ever been done to tame it,*o that it was impossible 

 to tell which were the original favourites, and which was the 

 new one. Moreover, when after a few years one of these jack- 

 daws was accidentally killed, another was brought by the other 

 two. 



