March i, 1906] 



NA TURE 



4i3 



LETTERS TO THE EDITOR. 



[The Editor does not hold himself responsible for opinions 

 expressed by his correspondents. Neither can he undertake 

 to return, or to correspond with the -.enters of, rejected 

 manuscripts intended for this or any other part of Nature. 

 Xo notice is taken of anonymous communications.] 

 Cooperation between Scientific libraries. 

 The note in Nature (February 15, p. 372) on Dr. T. 

 Muir's paper in the Proceedings of the Royal Society of 

 Edinburgh directs attention to a difficulty which, as you 

 rightly say, affects many others than the mathematicians 

 11I Scotland. You adduce, for example, Wales- but may I, 

 without giving offence to the Principality, veil lure to 

 suggest that the metropolis itself has still better claims to 

 dishonourable mention ? 



In the two sciences which chiefly appeal to me, geology 

 and zoology, the difficulty mentioned by Dr. Muir has long 

 presented itself forcibly, and there is a lengthy list of books 

 that I have been trying to see in vain, some of them for 

 more than five years. They are, so far as I can ascertain, 

 in none of the many libraries of this city. Naturally, the 

 remedy suggested by Dr. Muir long ago presented itself 

 to me, and I have lost no opportunity of urging it in con- 

 versation and in print. In view of your own recognition 

 of the importance of the subject, I venture to ask you to 

 reprint for a wider public the following paragraph from a 

 paper contributed to the Museums Journal for April, 1902. 

 After alluding to the cooperation between American libraries 

 in the matter of cataloguing, and to the specialisation 

 among the libraries of Chicago, I wrote : — 



" The extraordinary difficulty that a student has, even 

 in London, in seeing the literature of his subject — in fact, 

 the impossibility, unless he is prepared to spend large sums 

 of money on his private library — must have made many a 

 one long for the day when the learned societies and other 

 library authorities of London shall take this question of 

 cooperation in hand. To what end is all this fuss about 

 an international catalogue of scientific literature, with its 

 elaborate mechanism and enormous expense, if, when the 

 list of books is in his hands, it be still impossible for the 

 student to refer to them? The amount of money annually 

 spent by Government, through the libraries of the British 

 Museum, the Education Department, the Patent Office, 

 and the like, when joined with that spent by the great 

 societies, such as the Royal, the Zoological, the Linnean, 

 the Geographical, the Geological, with the College of 

 Surgeons and other public bodies of like character, is 

 surely enough, if properly administered, to buy the world's 

 output of books each year; and far more than enough, if 

 we remember that all publications of the United Kingdom 

 go to the British Museum as a matter of course, and that 

 the donation lists of many of these libraries are nearly as 

 big as their purchase lists. If only the money could be 

 pooled, and the purchases distributed according to some 

 pre-arranged scheme among the various libraries ; and if a 

 joint catalogue were prepared, and kept up from month 

 to month, showing not only the titles of books, periodicals, 

 and papers, but the libraries in which they were to be 

 found, then weary searching and fruitless wandering would 

 no longer be the lot of the conscientious student. Even as 

 things are, without so radical a reform as a redistribution 

 of income, I feel sure that a conference of librarians, bent 

 rather on furthering the interests of the reader than the 

 pride of their own institutions, and armed with the 

 necessary powers for cooperation, would soon lift London 

 libraries out of the hopeless muddle that we now have to 

 struggle with." 



I hope that now this subject has been taken up in vour 

 influential pages it will not be allowed to drop until those 

 concerned have at least attempted the remedy. 



F. A. Bather. 



The Blondlot «-Rays 



It would be interesting to know whether anyone has 

 obtained success in repeating the latest experiment designed 

 to show the objective reality of the n-rays, viz. that de- 

 scribed by M. C. Gutton in Comptes rendus for 

 January 15. 



The writer has repeated M. Gutton 's experiment with 



NO. I^q6, VOL. 73] 



much care, but has met with no more success in obtain- 

 ing any positive result than he has in repeating a large 

 number of M. Blondlot's own experiments, most of which 

 he has essayed, in all cases with absolutely negative 

 results, provided proper precautions were taken to avoid 

 effects due to temperature and other extraneous causes of 

 disturbance. 



According to M. Gutton's experiment, the effect of the 

 re-rays that proceed from a Nernst electric lamp upon a 

 spark in a primary circuit is to diminish the brilliancy 

 of another spark electrically induced in a secondary circuit 

 by the primary discharge. Here one would suppose that 

 the degree of brilliancy of the secondary spark can only be 

 a matter of the amount of the electrical energy in the 

 secondary circuit, but the writer finds that a very sensitive 

 Duddell thermo-galvanometer, which would indicate a very 

 small percentage of variation in the amount of this energy, 

 shows no variation whatever. 



A. A. Campbell Swinton. 



66 Victoria Street, London, S.W., February 20. 



A 300- Year Climatic and Solar Cycle. 



In June, 1902, I made a few remarks on an apparent 

 coincidence between sun-spot periods and longer periods of 

 rainfall and famine in north China. Not being, in any 

 sense, a meteorologist, I did not publish my conclusions 

 except locally. In connection with a notice in the " Astro- 

 nomical Column " of Nature, November 9 last (vol. lxxiii. 

 p. 38), they are of sufficient general importance to recall 

 them. The notice in Nature is headed " A 300-year Cycle 

 in Solar Phenomena," and refers to a discussion in the 

 Astrophysical Journal wherein Mr. H. W. Clough, of the 

 Washington Weather Bureau, arrives at the conclusion that 

 a 300-year cycle exists in solar and the allied terrestrial 

 phenomena, and finds likewise an intermediate 36-year 

 cycle, and supports both by a reference to various pheno- 

 mena, such as aurora;, periods of grape harvest, &c. 



In 1877 Mr. A. Hosie, H.M. Consul at Chengtu, pub- 

 lished a paper in the Journal of the China Branch of the 

 Royal Asiatic Society on droughts in China (new series, 

 xii., 51), extracted from Chinese records. As the records 

 included all China, south as well as north, the tables did 

 not at first sight exhibit any apparent periodicity. Some 

 years after, on making a careful division into north and 

 south, I was struck with a remarkable period of about 

 300 years, which seemed to me marked clearly in north 

 China as an especial era of drought and famine. As, how- 

 ever, there seemed no reason for founding a new period, 

 for the intercalation of which there was as yet no accumu- 

 lated evidence, I proceeded no further with the subject. 

 Mr. Hosie's paper went from the year 620 to 1643, cover- 

 ing a period of 1023 years, and attached to it was another 

 notice of sun-spots observed in China, also going back for 

 some 1300 years. The latter table, on account of the want 

 of anv observation instruments, is, of course, very frag- 

 mentary, but at the time I deduced from it without refer- 

 ence to European observations, which I had not by me, a 

 probable period of 99 maxima in the 1920 years covered, 

 which seemingly gave a mean of 11-085 years, an( l which, 

 produced to modern times, fell in sufficiently satisfactorily 

 with the European records of the last century. Sir Norman 

 Loekyer in 1901 had also published observations bearing 

 on a climatic curve of about six sun-spot periods, and 

 commenting on all these 1 made the following remarks, 

 whii li .ire entirely confirmative of Mr. Clough 's findings, 

 although deduced from such entirely different authorities. 



" I now come to the long period or era which Mr. 

 Hosie's records seem to require. The first of these calling 

 for notice seems to cover the three sun-spot periods 664- 

 697, though this is not so well marked as the others. 

 The second covers the similar period from the maximum in 

 963 to that in 996, when besides two years of drought in 

 northern China, 961 and 962, we find no less than twenty- 

 three years ojt of the thirty-three characterised by excessive 

 droughts in one or more of the northern provinces. The 

 third covers the periods 1262-1295, when, in addition to the 

 antecedent year 1260, there are noted twenty-one years of 

 drought in the same provinces. The fourth is included 

 between the spot maxima of 1561 and 1594, and though 

 not so marked as the second and third, yet ten years of 



