August i i , 1 904J 



NA TURE 



353 



the second child, but there is no conclusive evidence that 

 after a mother has had two children there is any change 

 in her tendencies. 



In the Monthly Review for August Mr. J. E. S. Moore 

 discusses " the cancer problem to-day," in which he details 

 recent investigations into the cytology of malignant 

 growths; and in the Fortnightly Review Dr. Alfred Mum- 

 ford writes on the alleged physical degeneration of the 

 race. The general trend of this article is that the deterior- 

 ation in the vigour and health of the British race as a whole 

 has been exaggerated, and that all the combined effort of 

 the past for the permanent improvement of the race cannot 

 have been without result. 



.\ I a special meeting of the Academia dei Lincei held 

 on June 5, the results of the competition, which closed on 

 December 31, 1902, for the royal prizes of the academy 

 were made known. In the section of philology, a royal 

 prize is awarded to Prof. .\. Trombetti for a work on the 

 genealogical connection between the languages of the 

 ancient world. The prize for astronomy is divided between 

 Prof. E. Millosevitch and Vincenzo Reina, and that for 

 philosophical science between Prof. Sante Ferrari and Prof. 

 Covotti. To celebrate the tercentenary of the academy, 

 which is the oldest institution of its kind in the world, it 

 is announced that Prof. Pirotta is preparing for publication 

 the botanical works of Prince Federico Cesi, who, with 

 Galileo Galilei, founded the Lincei in 1603. 



In the Physikalische Zeitschrift (No. 15) H. Mache 

 concludes that the emanation from the Gastein thermal 

 spring, which is so strongly radio-active, is identical with 

 that of radium, as the activity of both emanations decays 

 according to the same law. Moreover, the activity induced 

 in other bodies by the emanation from the water is of the 

 same character as that caused under similar conditions by 

 radium. In the same number E. F. Burton shows that 

 the diminution in the conductivity of air enclosed in a metal 

 vessel which is produced by surrounding the vessel with 

 water IS proportional to the thickness of the aqueous layer. 

 The view that the radiations causing the discharge come 

 from an external source is thus confirmed. It is also shown 

 that, on diminishing the pressure of air in the vessel 

 surrounded by water, the conductivity falls ofT continuously 

 witii the change of pressure. 



In the Physical Review for June, E. L. Nichols and 

 Ernest Merritt give an experimental confirmation of 

 Lommel's contradiction of Stokes's law that, in fluorescence, 

 the fluorescent light is always of greater wave-length thari 

 the e.Kciting light. The variation in the intensity of the 

 light throughout the fluorescence spectra of such substances 

 as fluorescein, eosin, and naphthalene-red was measured by 

 means of a spectrophotometer, and it is shown that, what- 

 ever be the wave-length of the exciting light, the curve 

 connecting intensity of light with wave-length in the 

 fluorescence spectrum is always of the same character. The 

 maximum of intensity in the excited spectrum may have a 

 wave-length much smaller than that of the exciting source. 

 Thus in the case of eosin, with an exciting light of wave- 

 length A 5S5-605, the maximum in the fluorescence spectrum 

 is at A 580, the whoFe spectrum extending from X 535 to 

 A 640. 



Part ii. of the Bulletin of the French Physical Society 

 for 1904 contains a description by A. Turpain of a new 

 apparatus for cleaning large quantities of mercury. The 

 NO. 18 I 5, VOL. 70] 



cleaning agent is a solution of mercurous nitrate, and the 

 mercury, after being cleaned, is dried by means of concen- 

 trated sulphuric acid, any free acid in the mercury being 

 subsequently removed by potash. The apparatus works 

 automatically during long periods, and needs little attention. 



In the July number of the American journal of Science 

 Mr. H. A. Bumstead describes experiments on atmospheric 

 radio-activity, which indicate that the activity acquired by a 

 negatively charged wire exposed in the open air at New 

 Haven, is of a two-fold character. From the rate of decay 

 it is concluded that thorium as well as radium excited 

 activity is present. With a three-hour exposure of the 

 wire, 3 to 5 per cent, of the initial effect is due to the 

 thorium activity, and with a twelve-hour exposure the 

 thorium activity is sometimes 15 per cent, of the whole. 

 -Messrs. Trowbridge and Rollins communicate that the 

 electrical resistance of an aluminium wire is not altered to 

 a measurable extent when subjected to the action of radium. 



The Geographical Journal for August contains a very 

 clear map showing the work of the National Antarctic Ex- 

 pedition. The map is the work of Lieut. Mulock, R.N., 

 who joined the Discovery from the Morning in February, 

 1903. The positions fixed by observations, magnetic 

 variations, soundings, heights, and the tracks of the sledge 

 travellers are clearly shown, as well as the track of the ship 

 to her furthest point along the coast of King Edward VII. 

 Land. An inset map shows the position of the discoveries 

 with reference to the circumpolar area. The same number 

 also contains the paper on " The German Antarctic Expedi- 

 tion " which was read before the Royal Geographical 

 Society in April last by Dr. E. von Drygalski. It is illus- 

 trated by some remarkable reproductions of photographs of 

 icebergs, &c. 



The current Century Magazine contains two contributions 

 which should be of interest to all students of nature, one, by 

 that careful American observer, John Burroughs, on " What 

 do Animals Know?" in the course of which a good deal 

 of out-of-the-way knowledge is given in a charming 

 manner the other, illustrated by some striking engravings 

 (one in colour), on " The Colossal Bridges of Utah," which 

 deals with the wonderful arches or natural bridges that 

 are to be found near the head of White Canon, in San Juan 

 County, Utah. One of these bridges, named by the dis- 

 coverers the Caroline, measures two hundred and eight feet 

 six inches from buttress to buttress across the bottom of 

 the canon. Its height is one hundred and ninety-seven feet 

 from the surface of the water, while its thickness at its 

 highest point is one hundred and twenty-five feet. The 

 floor of the bridge is one hundred and twenty-seven feet 

 wide, so that, as is pointed out, an army could march over 

 it in columns of companies, and still leave room at the side 

 for a continuous stream of artillery and baggage waggons. 

 Two other magnificent bridges, named respectively the 

 Augusta Bridge and the Little Bridge, are described and 

 figured in the article, which is well worth perusal. 



OUR ASTRONOMICAL COLUMN. 



Ephemeris for Encke's Comet. — A set of elements for 

 Encke's comet, corrected only for the Jupiter perturbations 

 of the first order between 1901 and 1904, is published by 

 MM. Kaminsky and Ocoulitsch in No. 3962 of the Astro- 

 nomische Nachrichten. These elements are given below, 

 together with an extract from a daily ephemeris for the 

 period August i to October 16 : — 



