January 13, 1916] 



NATURE 



547 



.cmical Society's Journal. The whole of. the circu- 



ing system is enclose<J, so that it can be immersed 



npletely in a thermostat, the riiovement of the liquid 



ing controlled by means of a scries of taps Connected 



a suctioq-pump. The capillary is arranged in a ver- 



il position, but contrary to the usual practice the 



How is in an upward direction, so that the risk of 



I partial obstruction of the capillary by particles of dust 



= - greatly diminished. The adjustment of the volume 



the flowing liquid is practically automatic and very 



act. A special tube with a tap is provided, whereby 



tiic liquid to be tested can be drawn from the centre of 



.1 stock-bottle after ample time has been allowed for all 



ices of sediment to settle; this is a marked improve- 



iit on pouring the liquid into the viscometer directly 



; from an ordinary pipette. The new viscometer has 



i' tn tested during several years of actual practice, and 



promises to take a permanent place alongside the 



jivknOmeter and the stills for conductivity-water, 



\\ hich have already been described by the author. 



The University of Chicago Press has in preparation 



early publication in the " University of Chicago 



i«ince Series ":—" The Origin of the Earth," by 



uf. T. C. Chamberlin, and " The . Isolation and 



Measurement of the Electron," by Prof. R. A. Miili- 



kan. The volumes will be issued in this country by 



Cariibridge University Press. 



OVR ASTRONOMICAL COLUMN. 



("o.MET 19156 (Taylor). — This comet has been under 

 -ervation a number of times at the Hill Observa- 

 r\ since the beginning of the year. It has slowly 

 mcreased in brightness. The ephemeris given below 

 (No. 498, Eph. Zir., Astronomische Nachrichten) is 

 based on the second orbit calculated by Messrs. Braae 

 and Fischer-Petersen, and is for i2h. M.T. Green- 

 wich : — 



Jiti. R.A 8 Jan. K.A S 



2 47 +13 8-0 18 5 2 28 -I- 16 13-9 



2 30 14 9-1 20 2 44 17 172 

 2 24 IS III 21 3 13 ' 18 209 



The R.A.'s increase after January i6. The comet 

 continues to approach the sun. An observation on 

 Jianuary 7 showed that the ephemeris then required cor- 

 rections of +27 min. in R.A. and —43" in declination. 

 It may be remarked that it is moving through a region 

 devoid of bright stars — N. and W. of Bellatrix. 



We have received the following upon this corriet from 

 the Union Observatory, Johannesburg, December 9, 



On December 2, 1915, Mr. Clement J. Taylor, of 



Herschel View, near Capetown, reported to the Union 



Observatory, Johannesburg, he had found a comet in 



'ion on November 24, and that it was near 31 Orion, 



i moving northwards. It was observed on the same 



• <:ning and subsequently. The 1915-0 astrographic 



} Lsitions obtained at the Union Observatorv* are : — 



Green-iVich Time. 



m lyiS t. m. s .. . « ■ 



■ Dec. 2347 ... 5 24 45-9 o 39 6 

 I 4325 — • 5 23 So-3 ••• o 2J 48 

 I 5-347 5 23.19-9 . -•• o 12 12 



■ . Co.MET 1915a (Mellish). — Some measurements of the 

 ■additional nuclei of Mellish's comet (1915a) have been 



Hnnade- by Mr. Knox Shaw (Helwan Observatory Bulle- 



" ^in, No. 16), The nuclei were situated on a bright 



in the tail, the one more distant from the head 



96] 



being the brighter, and in the later stages appeared 

 to be subdividing. ' During May these extra nuclei 

 receded^ from the head with daily motions of about 

 looo km. 



The Spectrum of the'Bik.vry System 41 Eridani. — 

 In Bulletin No. 274, Lick Observatory, Dr. G. F. 

 Paddock investigates the question of spectroscopic orbit 

 formulae, especially considering the derivation of 

 elements of nearly circular orbits, and the reduction in 

 cases where spectra of both comix)nents are available. 

 In the first case, he irriproves the dfetermination of 

 position and epoch of periastVon, and in the second 

 enables the reduction bi the double measures to be 

 carried on as one operation ' ih$tead^-6f using them tcv 

 obtain two symmetrical solutiorrs!*^"The new formulae- 

 have been put in use in a stUdy^df the spectroscopic 

 binary 41 Eridani (mag. 3-9, S^p. B9A). Briefest 

 reference only can be made to some of the many 

 important questions dealt with. A definite value is 

 adopted for the wave-length of the magnesium line— • 

 4481-400 A., or 4481-230 I. A., and the variations of 

 wave-length of this line alone are employed in deducing, 

 the orbit. All the thirty-nine spectrograms employed 

 show it as a double line due to the two component 

 sjjectra. The system proves to be one of normal 

 values, although accurate photometric measures are 

 yet required to fix the inclination of the orbit-plane. 

 Measured wave-lengths are given for fifty lines (K tc^ 

 H/8) and origins discussed. The lines are stated to be 

 not so sharp as in Sirius, and distinctly fainter. A 

 noteworthy feature is the number of proto-Mn lines- 

 represented. Intensities are merely verbally described. 

 Two notes on the table of wave-lengths call for special 

 remark. First, Mr. F. E. Baxandall, in 1914, pub- 

 lished several new enhanced lines of Mn, including one 

 at A 4282-65. This origin will account for the line at 

 A 42827. Secondly, the line A 44x6-9, although masked 

 in spark spectra, was shown by Prof. A. Fowler to be 

 an enhanced line of iron, and provided a recognised 

 origin for the stellar line. These points only emphasise 

 the conclusion that 41 Eridani has an essentially 

 enhanced line spectrum. ' ' ' ' 



The Constants of the Terrestrial Spheroid. — 

 The Paris Conference (1911) adopted Hayford's values 

 for the equatorial radius and aplatissement. Since, 

 then Helmert has derived a new value for the radius, 

 and S. Wellisch suggests that Hayford's and Hel- 

 mert's results should be combined. Instead of taking 

 the adopted Hayford values he proposes that the mean, 

 be taken of three sets of values based on different 

 assumed depths of the i.sostatic compensation layer 

 162-2 km., 1209 km., and 113-7 km.). Taking 'Hel- 

 mert 's values with weight = unity, and the modified 

 Hayford values with weight = 4, he obtains for the 

 equatorial radius = 6,378,372 metres, excess over polar 

 radius = 2 1, 476 metres, whence the reciprocal of the 

 aplatissement = 297. The length of the "metre" de- 

 rived from these values is 1-00022632 metres {Astro- 

 nomische Nachrichten, 4822). 



SCIENCE AT EDUCATIONAL 

 CONFERENCES. 



" \117HAT difference has the war made? I believe 

 ' ' it has opened the eyes of the nation to the 

 perils which arise from the neglect of intellectual 

 things, the satisfaction with book knowledge, the in- 

 attention to facts, the concentration on physical 

 prowes!«, ai>d on a passive kind of material prosperity — 

 the widespread ignorance of natural facts even among 

 our leaders, and consequent contempt for investigation 

 and expert knowledge. -What has become apparent is 

 the ignorance, of our governing- classes. The ignor- 

 ance of all classes. The facts that education has not 



NO. 241 1, VOL. 



