October 29, 19 14] 



NATURE 



239 



ships. The ship is of the twin-screw, single-deck 

 t\pe, and is designed for a speed of 14 knots when at 

 a loaded displacement of 19,230 tons. In addition to 

 having interesting equipment for the handling of coal 

 and oil fuel, the vessel is notable, as the propellers 

 are driven by electric motors, current being supplied 

 to these by turbine-driven generators, the shaft-horse- 

 power available for propulsion being 5500. The total 

 cargo capacity is 966,260 gallons of oil and 9856 tons 

 of coal, or, alternatively, 405,620 gallons of oil and 

 11,380 tons of coal. The coal handling gear was sup- 

 plied by the Mead Morrison Manufacturing Company, 

 and the stipulation of the contract was for the deliver)' 

 of 100 tons per bucket per hour when the gear was 

 operated by winchmen of one week's experience. 

 Owing to the large number of tow'ers supporting the 

 booms and rigging of the coal handling plant, the 

 appearance of the vessel is somewhat unusual. 



The Scientific American for October 3 draws a 

 contrast between the ordinarj- European frontier with 

 ■rs enormous forts and lines of strategic railways, and 

 :he Canadian frontier. On the continent of America, 

 the two greatest nations of the world have a common 

 frontier which extends, unbroken, for some 4000 miles. 

 Throughout the w-hole of this frontier there is not to 

 be found, on either side, a single fortification, or any 

 offensive or defensive military work of any kind 

 whatsoever, and this is the case despite the facts that 

 this far-f!ung frontier was the eventual outcome of a 

 fierce war, and that these two powerful nations have 

 always been engaged in keen comm^'-ial rivalry'. 

 That heavily fortified frontiers, backed by military 

 railways, are a menace to a friendly neighbouring 

 State, and provocative of responsive military works, 

 and that they produce an atmosphere of international 

 -uspiclon and dislike cannot be disputed. There is a 

 g^rowing conviction that the failure of the Teutonic 

 attempt to establish a military dictatorship in Europe 

 will be followed by the final subjugation and control 

 of militarism. Our contemporary can think of no 

 cjuarantee that would be more effective than the com- 

 plete obliteration of these fortifications, modern in 

 construction, but essentially medieval in conception, 

 which disfigure European frontiers. 



Messrs. Johx Bartholomew and Co., of the Geo- 

 graphical Institute, Edinburgh, have published a new- 

 reduced survey map of north-eastern France, Belgium, 

 and the Rhine. The map is coloured orographically, 

 and is on the scale of sixteen miles to an inch. This 

 scale makes it possible to show w'ith clearness the 

 railways, fortresses, main and secondary roads, and 

 frontier custom-houses. Heights are given both in 

 metres and feet, and the distances between road 

 unctions are marked. The price of the map is 2s. on 

 ;iaper, and 35. mounted on cloth. 



The following forthcoming books of scientific in- 

 terest are announced by Messrs. G. Bell and Sons, 

 Ltd. :— X-Rays and Crystal Structure, by Prof. W. H. 

 Bragg; Quantitative Laws in Biological Chemistry, 

 by Prof. Svante Arrhenius ; Tuberculosis : a General 

 Account of the Disease, its Treatment, and Prevention, 

 by Dr. A. J. Jex-Blake ; Woollen and Worsted Cloth 

 NO. 2348, VOL. 94] 



Manufacture, by Prof. R. Beaumont, illustrated; 

 Buddhist Psychology, by Mrs. Rhys Davids. The list 

 of Messrs. Methuen and Co., Ltd., includes : — Mv 

 Life, by Sir Hiram S. Maxim ; On Alpine Heights and 

 British Crags, by G. D. Abraham, illustrated ; How- 

 to Know the Ferns, by S. L. Bastin, illustrated; 

 British Insects and How to Know Them, by H. 

 Bastin, illustrated; The Mammary Apparatus of the 

 Mammalia in the Light of Protogenesis and Phylo- 

 genesis, by Prof. E. Bresslau, illustrated; Mind Cures, 

 by G. Rhodes ; and the following first volumes of 

 Methuen 's Health Series : — The Eyes of Our Children^ 

 by N. B. Harman ; Throat and Ear Troubles, by M. 

 Yearsley ; The Teeth, by A. T. Pitts ; The Care of the 

 body by Dr. F. Cavanagh; The Health of a Woman, 

 by Dr. H. J. F. Simson ; Health for the Middle-Aged, 

 by Dr. S. Taylor; The Prevention of the Common. 

 Cold, by Dr. O. K. Williamson ; and The Hygiene 

 of the Skin, by Dr. G. Pernet. 



OUR ASTRONOMICAL COLUMN. 



The Rotation- Periods of tw-o of Saturn's 

 Satellites. — In the Bulletin (No. 64) of the Lowell 

 Observaton,' Prof. Lowell and Mr. Slipher publish 

 their observations in relation to two of the satellites of 

 Saturn, namely, Mimas and Enceladus, which have 

 led them to deduce that the revolutions and axial rota- 

 tions of these bodies are synchronous. This investiga- 

 tion on the brilliancy of these satellites was carried out 

 in December, 1913, and the first three months of the 

 present year, and resulted in finding out that these 

 bodies are of very unequal albedo in different parts of 

 their apparent orbits, and the variations recur in situ 

 showing that the satellites always turn the same face 

 to their primary. Both the moons appear brightest 

 near their western elongations and faintest near their 

 eastern. Their magnitudes and ranges are giv-en as 

 follows : — Mimas, 12-90 to 13-33 » Enceladus, 12-33 to 

 12-67. Both these bodies are too small to show a disc, 

 so their size has been inferred from their brilliancy 

 relative to Tethys. Tw-o figures accompany the text, 

 in which the observations are plotted diagrammatic- 

 ally. 



Difference of Longitude between Paris xsd Nice. 

 — In a communication by M. B. Jekhowsky, presented 

 to the Paris Academy of Sciences {Comptes rendus. 

 vol. clix.. No. 15, October 12) by M. P. Appell, a brief 

 summary is given of the determination of the differ- 

 ence of longitude between Paris and Nice. The astro- 

 nomical observations have been made at both these 

 stations with the "module g^od^sique de I'astrolabe a- 

 prisme," by the eye and ear method, and the chrono- 

 metric comparisons w-ere made by wireless after the 

 method of MM. A. Claude, G. Ferris, and L. Drien- 

 court. The chronometer rates were controlled both 

 before and after the astronomical observations by 

 pendulums, and comparisons were made at the begin- 

 ning and end of each series of obser\'ations. The 

 daily wireless time signals from the Eiffel Tower were 

 utilised as a check on Paris and Nice chronometers 

 between the two series of evening observations. The 

 observations were made on the evenings of May 3, 6, 

 31, and June 5, and the final result of the difference 

 of longitude between Paris and Nice is given as 

 oh. 19m. 5 1 •204s. ± 006s. 



Effect of Humidity on Photogr-iphic Pi_\tes. — It 

 has been previously pointed out that when a photo- 

 graphic. plate has been exposed in a telescope for some 

 time the plate gradually loses some of its sensitiveness. 



