December 7, 1905] 



NA TURE 



135 



A useful series of memoirs is being published monthly 

 in the Bulletin du Musee oceaiwgraphiquc de Monaco. In 

 No. 44, for October, Prof. Hergesell discusses some future 

 problems of maritime meteorology ; by this name he refers 

 to the meteorological phenomena of the atmosphere over 

 the oceans. He remarks that if our knowledge is well 

 advanced over the land, it is much less so over the oceans, 

 and that our knowledge over the sea is due to a great 

 extent to such expeditions as those of the Challenger, 

 Gazelle, and Valdivia. Others might have been cited, e.g. 

 the Austrian expedition of the Novara in 1857-9. But we 

 cannot help remarking that the meteorology over the oceans 

 might be considered as fairly well defined, owing to the 

 labours during the last fifty years of such men as Maury 

 in the United States, FitzRoy and Toynbee in this country, 

 Leverrier and Brault in France, Buys Ballot and Andrau 

 in Holland, Neumayer in Germany, and, of course, in- 

 cluding their successors in the central meteorological offices 

 of the respective countries. But while much has been done 

 in the investigation of the upper air over the land by the 

 use of kites and balloons, both manned and unmanned (or 

 " sounding " balloons), and some surprising results have 

 been obtained, little has yet been done in this respect over 

 the oceans. The balloon ascents over the land have shown, 

 for instance, that there is a warm stratum of air at a 

 height of about 11 kilometres; that the decrease of tempera- 

 ture with altitude ceases more or less abruptly, and that the 

 temperature actually increases for a further height of several 

 kilometres. This zone of inversion is probably intimately 

 connected with the general circulation of the atmosphere, 

 and it is most important to know the exact conditions 

 over the ocean, especially in equatorial and certain other 

 localities. We are glad to see that the Prince of Monaco 

 has succeeded in interesting the Emperor of Germany in 

 these questions, and that the cooperation of the German 

 Navy in elucidating them appears to be assured. 



Of the papers read at the optical convention in June 

 last, a number of those having a special bearing on the 

 microscope are abstracted in the Journal of the Royal 

 Microscopical Society for October. In one of these papers, 

 dealing with equivalent planes of optical instruments, Mr. 

 Conrad Beck gives a simple explanation of the why and 

 wherefore of the particular arrangement of lenses adopted 

 in the compound microscope. A high-power microscope 

 may have an equivalent focal length of only a few 

 thousandths of an inch, but the plan of using lenses 

 separated by large intervals gives an instrument in which 

 the equivalent planes (i.e. the principal planes) are outside 

 the system of lenses, thus allowing sufficient working 

 distance between the front lens and the object. 



In connection with Prof. Paul Harzer's recent communi- 

 cation to the British Association (vide Nature, October 26), 

 we read with considerable interest an address delivered by 

 him at the University of Kiel on the Emperor's last birth- 

 day, published by Lipsius and Tischer, of Kiel, dealing with 

 the development of exact sciences in ancient Japan. In the 

 Imperial Library of Tokyo there are no less than 2000 

 written and printed Japanese mathematical works extend- 

 ing back to the year 1595 ; and it is scarcely remarkable 

 that the determination of the " Ludolphian Number " (Pi) 

 played a prominent part in the thoughts of early Japanese 

 mathematicians. In 1627 the approximation 79/25 was 

 known, while in the second half of the seventeenth century 

 values had been obtained which are correct to 9 or 10 

 places. ' The well known value 355/113 was known in 

 1709, and in 1722 and 1739 values correct to 49 and 51 

 places had been found. Among the early " circle 

 scuarers " Kowa Seki (1642-1708) occupied a leading place. 



no. 1884, vol. 73] 



His methods, which were applicable to circular arcs 

 generally, depended on successive bisection, but in solving 

 the quadratic equations by means of scries the binomial 

 expansion of the square root was used. During the 

 eighteenth century four series for Pi were known to 

 Naomaro Ajima, who also dealt with the ellipse. At the 

 beginning of the nineteenth century Enzo Wada was 

 acquainted with the catenary and cycloid, and it now 

 appears proved that Seki and his immediate successors 

 studied the binomial theorem, theory of numbers, the 

 properties of maxima and minima, determinants, and 

 spherical trigonometry. Of geodetical observations we 

 have records dating from 1613, and these culminated in 

 the measurements of arcs of the meridian by Ino 

 Chukei (?) in 1800-1818. On the other hand, even as late 

 as 1895, Prof. Harzer finds complaints of the neglect of 

 higher mathematical study in Japan. The question as to 

 how far the ideas of the early Japanese mathematicians 

 were imported from the west through the medium of the 

 Dutch trading ships or other means occupies a prominent 

 part in Prof. Harzer's dissertation. 



The twenty-fifth number (n.s.) of the Transactions of the 

 Oxford University Junior Scientific Club contains, in 

 addition to a list of the officers and new members and 

 balance sheet, a paper by Mr. A. F. Walden on some 

 recent views on the constitution of inorganic compounds, 

 which gives an account of Werner's ideas as to the nature 

 of complex cobalt and chromium salts. Mr. A. S. 

 MacXalty deals with trypanosomiasis and sleeping sick- 

 ness. 



In No. 18 of the Revue ginirale des Sciences M. Bernard 

 Brunhes, director of the Observatory of Puy-de-D6me, gives 

 an interesting account of recent work on terrestrial mag- 

 netism in central France. Notice is taken of the anomalies 

 met with by workers in other countries, and particular 

 emphasis is laid on the tendency of magnetic rocks to 

 produce these effects. The Puy-de-D6me affords' an 

 especially good example of the influence of magnetic rocks 

 on the terrestrial magnetism of a district. A description 

 is given of the method adopted in measuring the declin- 

 ation and inclination due to the permanent magnetisation 

 of the specimens of rock selected for experiment. 



The delegates of the Clarendon Press, Oxford, have pub- 

 lished in pamphlet form, at sixpence net, an addendum to 

 Mr. J. Cook Wilson's " On the Traversing of Geometrical 

 Figures," which was reviewed in the supplement to our 

 issue of October 19 (p. vi). 



We have received from Messrs. A. Gallenkamp and Co., 

 Ltd., of Sun Street, Finsbury Square, London, a copy of 

 the fifth edition of their general chemical and scientific 

 apparatus catalogue, which has been arranged to meet the 

 requirements of the session 1905-6. The catalogue runs 

 to 534 pages, and is profusely illustrated with clear and 

 helpful illustrations. The arrangement of prices and 

 details of sizes and similar facts in a simple tabular form 

 throughout, and the concisely expressed descriptions of the 

 forms of apparatus available, reduce the trouble of refer- 

 ence to a minimum. There is a good index provided also. 

 Special attention may be directed to the section giving 

 particulars of many forms of electrochemical apparatus, 

 which should prove of interest to teachers and students 

 of electrochemistry. The catalogue is worth examination 

 by teachers who have charge of chemical and physical 

 laboratories, and also by men of science engaged in research 

 work. The excellence of this and other similar catalogues 

 which have come before us recently is instructive evidence 

 of the progress which has been made in the teaching of 

 science in our schools and colleges. 



