February i, 1906] 



NA TURE 



325 



Darya, Samarkand, Ferghana, Semirechi, and Trans- 

 Caspian districts. This in itself shows the immense 

 sacrifices the natives are called upon by the authorities to 

 make in connection with the destruction of locust eggs. 

 Between the years iqoo and 1905 the rural authorities of 

 those localities paid away sums to the amount of 80,000/. 

 for the destruction of locusts, and yet during this period 

 the crops in Central Asia were damaged to the extent of 

 150,000/. by this insect. 



The publication in Nature of December 7, 1905 (p. 132), 

 of some verses on the passing of the atom, sung at the 

 chemical laboratory dinner at University College, London, 

 has induced Mr. F. Horton, St. John's College, Cambridge, 

 to send us a copv of the post-prandial proceedings of the 

 Cavendish Society, containing several metrical compositions 

 inspired by recent work on ions and radio-activity. Songs 

 of this kind are sung at the Cavendish research students' 

 annual dinner, which is held at the end of each Michaelmas 

 term ; and the one by Mr. A. A. Robb reprinted else- 

 where in this issue is a good example of versification in 

 science. 



In two recent papers, the one by Mr. D. Himstedt and 

 Mr. G. Meyer, published in the Berichte of the Freiburg 

 Scientific Society (1905, vol. xvi., p. 13), and reprinted in 

 Lc Radium (vol. ii., No. 12), the other by Prof. B. Walter 

 and Mr. R. Pohl [Annalen del Pkysik, iv., 18, 406), ex- 

 perimental evidence is brought forward to show that the 

 light ordinarily emitted by radium bromide is principally 

 due to the impact of the Becquerel rays on the particles 

 of nitrogen in the immediate vicinity. The probability of 

 this being the case was suggested by Sir William and 

 Lady Huggins in 1903, although the latter were unable 

 then to obtain direct evidence in support of their view. 



An important paper by Prof. A. W. Witkowski on the 

 thermal dilatation of compressed hydrogen is published in 

 the Bulletin International of the Cracow Academy of 

 Sciences (1905, No. 6). Full details are given of the 

 methods employed in determining the values, already pub- 

 lished in a brief report to the British Association in 1904, 

 of the volume coefficient of dilatation of hydrogen at tem- 

 peratures ranging from +100° to — 190 C. under pressures 

 of 1-60 atmospheres. The results are used in discussing 

 Wroblewski's calculation of the critical temperature and 

 pressure of hydrogen, a subject which is also dealt with 

 experimentally by Prof. Olszewski in the following number 

 of the Bulletin (1903, No. 7). The critical pressure was 

 found in a new determination to be 13-4—15 atmospheres, 

 the critical temperature being — 240°-8 C. Prof. Olszewski 

 also describes in No. 7 an unsuccessful attempt to liquefy 

 helium by allowing it to expand suddenly, after cooling to 

 — 259 C. by means of solid hydrogen, from a pressure of 

 180 atmospheres. Not a trace of liquefaction could be 

 observed at the temperature obtained in this way, which 

 is calculated to be as low as — 27i°-3 C, or i°-7 absolute. 



At the last meeting of the physical-mathematical section 

 of the Berlin Academy of Science, held under the presi- 

 dency of Prof. Waldeyer, Prof. Landolt epitomised the 

 results of his extensive experiments on the question of the 

 possible change of weight caused by chemical action, and 

 stated that he had obtained confirmation of many previous 

 observations of a decrease in weight as a result of certain 

 reactions, and that he had started further experiments with 

 the view of discovering the cause of such changes. Prof, 

 van 't Hoff gave a further contribution to his series of 

 papers on natural salt formations, xlv., the occurrence of 



NO. 1892, VOL. 73] 



tincal and octahedral borax. In collaboration with Bias- 

 dale he had observed that the appearance of octahedral 

 borax in Italy was dependent upon a minimum tempera- 

 ture of about 35°-5 C. Prof. Waldeyer read a communi- 

 cation from Dr. A. Sachs, of Breslau, on Weinke, a 

 hexagonal mercury oxychloride from Terlingua, in Texas. 

 This mineral, to which the formula Hg.CLO., is given, is 

 a ehird addition to the other two mercury oxychlorides 

 previously found in this district, namely, eglestonite, 

 Hg,.Cl,0,, belonging to the regular system, and the mono- 

 clinic terlinguaite, Hg,C10. 



The real existence of the n-rays, discovered by M. 

 Blondlot, has been the subject of much discussion, there 

 being a general consensus of opinion outside France that 

 the effects produced are physiological. The Comptes rendus 

 for January 15 contain two papers of considerable interest 

 on this subject. The first of these, by M. Mascart, gives 

 details of a series of measurements of the points of 

 maximum intensity in the spectrum produced by the re- 

 fraction of the 11-rays through an aluminium prism, by a 

 number of independent observers. The phosphorescent 

 screen was mounted on the carriage of a dividing engine, 

 and each of four observers (Messrs. Blondlot, Gutton, 

 Virtz, and Mascart) made independent measurements of the 

 points of maximum intensity. The most concordant figures 

 were those obtained by M. Blondlot, but the general agree- 

 ment of the results left no doubt as to the position of the 

 lines. M. Mascart gives the results without comment. 

 The second paper, by M. Gutton, is an attempt to prove 

 the objective existence of the 11-rays. It had been noted 

 that if these rays are allowed to fall on the primary spark 

 of a Hertzian oscillator, the lustre of the secondary spark 

 diminishes. This effect has been secured photographically, 

 the difference being clearly marked in the whole of the 

 thirty-seven experiments. The apparatus is described in 

 detail, and the precautions necessary for success pointed 

 out. These two papers certainly provide material for con- 

 sideration bv those who maintain that the whole pheno- 

 menon is a physiological illusion. 



Prof. Henri Moissan has continued his experiments on 

 the fusion and volatilisation of the more refractory metals 

 in the electric furnace, and gives an account of his results 

 in the current number of the Comptes rendus (January 22). 

 In the first experiment, made with osmium, the tempera- 

 ture obtained by using a current of 500 amperes at 110 

 volts, although sufficient to distil 16 per cent, of the metal 

 in four minutes, was not sufficient to melt the metal, 

 except at the edges. Osmium was entirely fused with a 

 current of 700 amperes at no volts in five minutes, but 

 the fused metal contained nearly 4 per cent, of graphite. 

 Under the same conditions of current and voltage as in 

 the second experiment above mentioned, 150 grams of 

 ruthenium were completely melted in three minutes, about 

 11 per cent, being distilled during the fusion. The fused 

 ingot of ruthenium also contained graphite. Platinum 

 could be distilled in the same furnace with great ease, 

 and, indeed, Prof. Moissan remarks :— " The liquid metal 

 distils with the same facilitj as water carried to 100° C." 

 Palladium, iridium, and rhodium were also fused and dis- 

 tilled without difficulty, palladium being the easiest metal 

 to fuse of all those examined in this group. 



A SUMMARY of the weather tor 1905 at Sevenoaks has 

 been received from Mr. W. W. Wagstaffe. 



Mr. H. K. Lewis's quarterly list of new books and new 

 editions added to his Medical and Scientific Library 1130 

 Cower Street, W.C.) during the last three months of 1905 



