424 



NA TURE 



[March i, 1906 



" laminage " in connection with problems of thermal 

 conductivity between gases and solids; also improvements 

 in the construction of boilers and surface condensers based 

 mi the same study, having for their object the construction 

 of light motors for aerial navigation. Then, again, we find 

 Renard turning his attention to portable hydrogen gener- 

 ators fcr military ballooning and pneumatic elevators foi 

 grain and other materials. Last, but nut least, we have 

 the motor train, exhibited in December, 1903, all the 

 carriages of which were self-propelled by power transmitted 

 from the motor through a series of jointed shafts. This 

 train was successfully conducted round sharp corners 

 through the streets of Paris. 



The February number of Symons's Meteorological 

 Magazine commences the forty-first volume of this useful 

 periodical. It began as a two-page " Rain-circular," in- 

 tended to keep rainfall observers in touch with each other's 

 work ; in 1S66 it became an eight-page magazine, and has 

 now gradually increased to twenty pages, and has attained, 

 under the editorship of Dr. H. R. Mill, to the position 

 of one of the most important monthly meteorological 

 reviews published. Dr. Mill points out that the readers 

 of the magazine frequently tender advice ; although 

 this cannot always be adopted individually, he has 

 endeavoured to give effect to the principal desiderata put 

 forward during the last few years. The chief result has 

 been the introduction ol a very useful additional table of 

 fifty-four rainfall stations, giving the position and height 

 above sea, and the statistics of rainfall and temperature 

 for each month ; it shows the value and dat r * of the 

 maximum and minimum temperature, and the number of 

 nights at or below 32', both in the shade and on the 

 grass; the thirty years' average and the actual rainfall 

 for the month, the greatest fall in twenty-four hours, and 

 the number of rainy days, together with the mean annual 

 fall. Following numbers will show, somewhat like the 

 Weekly Weather Report of the Meteorological Office, the 

 total rainfall from January 1 to the end of the month 

 dealt with. This new table involves a considerable amount 

 of additional labour, but greatly enhances the value of the 

 publication. 



A very interesting article on the uranium deposits of 

 St. Joachimsthal is contributed by Dr. Paul Gaubert to 

 No. 1 of vol. iii. of Le Radium. The article is illustrated 

 by geological maps of the district and of the mines, and 

 by two photographs of the town. The same number of 

 Le Radium contains also a risumi, by Prof. G. Sagnac, of 

 the experimental methods used in the study of the trans- 

 formation of Rontgen rays. 



The report of the International Committee on Atomic 

 Weights for 1905 is published in the Proceedings of the 

 Chemical Society (vol. xxii., No. 303)- During the past 

 year there was unusual activity in the determination of 

 atomic weights, and sum.- of the work dune relates to the 

 most fundamental values. The entire system of atomic 

 weights is thus affected more or less profoundly, and a 

 general revision would seem to be needed in the near 

 future. In particular, thi recenl re-determinations of the 

 atomic weights of chlorine, sodium, and nitrogen appear 

 to show that the values obtained by St. is for these elements 

 are now no longer hnable. Guye's work in connection 

 with nitrogen has alread) b en noticed in Nature (vol. 

 lxxiii., p. 37). The other elements of which the atomic 

 weights have been re-determined are cadmium, carbon, 

 gadolinium, iodine, potassium, silicon, strontium, tellurium, 

 and thorium. 



NO. 1896, VOL JT,] 



Some interesting results have been obtained by Mr. 

 Percival Lewis in studying the degree of ionisation in the 

 gases resulting fnun coloured flames (Physical Review, 

 vol. xxi., No. ti). The specific ionic velocity was measured 

 in the ease of a Hunsen flame into which solutions of 

 known concentrations of various salts ,,[ the alkalis and 

 ilkalii - earths were sprayed. The ionic velocity apparently 

 varies in the ease of each salt inversely as the square 

 net of its concentration in the flame; the specific ionic 

 velocity lias, moreover, the same magnitude for ions of 

 tlie same sign from equimolecular solutions of all the 

 sails cil all the alkali metals. The velocity of the negative 

 ions is always somewhat greater than that of the positive 

 ions. The measurements given show also that the rate 

 of re-combination of the ions from the colourless Bunsen 

 flame is much greater than that observed in the case of 

 the coloured flames. 



Prof. Henri Moissan in a recent paper gave an account 

 of his experiments on the fusion and distillation of metals 

 of the platinum group. In the current number of the 

 Comptes rendus (February 19) he describes similar experi- 

 ments on the metals of the iron group, the metals examined 

 including nickel, iron, manganese, chromium, molybdenum, 

 tungsten, and uranium. All these were distilled in the 

 electric rumace, but the boiling points varied considerably. 

 The incst volatile proved to be manganese, which distils 

 readily before the b'aie of the furnace is volatilised. Nickel 

 is fairly easy to distil, then chromium, which distils with 

 regularity under the action of a current of 500 amperes at 

 no volts. Iron offers difficulties, on account of the dis- 

 solved "as causing foaming at the commencement of dis- 

 tillation, but with a current of 1000 amperes at 110 volts 

 _|oo grams ol iron distilled in twenty minutes. The boiling 

 point of uranium is higher than that of iron. The greatest 

 difficulty was experienced with molybdenum and tungsten ; 

 the latter metal, with a current of 500 amperes at no volts, 

 showed no si^ns ol fusion in five minutes; even when the 

 current was raised to Soo amperes only 23 grams could be 

 distilled in twenty minutes. 



Dr. G. II. Fowler desires it to be known that the 

 Marseilles Exhibition of Oceanography and Sea Fisheries 

 has not been " postponed," as stated in a circular issued 

 by the British Commission of the Milan Exhibition. No 

 postpi nement of the Marseilles Exhibition has been con- 

 templated, though H.M. Treasury has refused financial 

 support. 



Messrs. Sampson Low, Ltd., have just published the 

 eighth edition of Mr. W. T. Lynn's' " Remarkable 

 Eclipses " and the thirteenth edition of his " Remarkable 

 Comets." Each book, though it contains only about fifty 

 pages, five's an interesting and accurate statement of the 

 main facts of the subject with which it deals. 



I 111 Countrj Press, Ball Street, Kensington, W., has 

 issued a series of seven pictorial post-cards on which 

 .ue -hown in an effective manner forty-two species of 

 British ferns. The idea is a good one, and should serve 

 0, direct the attention of young people to the beauties of 

 this branch of plant life. Other natural objects are to be 

 dealt with in a similar manner in future series of post- 

 cards. 



We have received a copy of the thirty-seventh annual 

 report of the Wellington College Natural Science Society, 

 that, namely, for 1905. It is quite clear that the society's 

 activity has in no way diminished. The open Saturday 

 meetings provide the boys of the school with excellent fort- 

 nightly lectures, the subjects of which are by no means 



