IBEB 24, [918 



NATURE 



'5. 



Millais, with sixteen full-page illusir.iii.ni-; ship-' 



["heir Qualities, Construction, Equipment, 



and Launching Appliances," E. W. Blocksid 



a new an. I revised edition of "Recent Vdvances in 



Physical and Inorganic Chemistry," l>r. A. VV. 



Stewart, with an imr.Kluni.in In the late Sir William 



. K ( :.B . 1 .R.S., illusti 



Mr F. Edwards, of 83 High Street, Marylebone, 



issued Catalogue No v s i of 1 ks dealing 



with a variety of subjects, l>ui mainh architecture, 



ography, and bookbinding. Hi. 



sections special] eaders ol 



\uiRi are thsse relating to archaeology, gardens, 



.-iiiil the proceedings of man) provincial scientifii 



ies 



Messrs. J. M. I >bn r and S 



n the Controllei ol Patents to publish 

 1 "The Biolog) ol War," by Prof. G. F. 

 Ni.linl.ii, the former .bolder of the chair of physiology 

 in Berlin University, who, after imprisonment in Ger- 

 man) for his opinions, escaped to Denmark bj aero- 



OUR ASTRONOMICAL COLUMN. 



1 lv's Comet. — L. v. Tolnay gives the fol- 

 lei lents of this cornel in Astr. Nach. 

 ; hi has computed planetary perturbations, 



including those of Mars, to which il reel mad. 



i: al the beginning of 191 2 : — 

 T = ioi8 Nov. 16-6818 G.M.T. 

 <•> =352' -i 073 I 

 Sl= 77 ' 4-71 . 19250 

 / = 30' 29' 2901 j 

 <t> = 37 

 /i =5i3 - 9o8i6' 

 The following ephemeris is from a M 1 -ill.- > ir- 

 ir t ireenwich midnight 1 : 



R.A. Loj J 



d Bulletin (No. 669) gives the following ob- 

 3 made al th. Yerkes Observatory by Mr. Van 

 ck : — 



r, \ 



h. in. -. , „ 



' I 



Sep 4 45 18-78 13 29 474 



I id a diffused 1 longated nui leus in P. \. 95 , 

 long in the sam.' direction; its magnitude 

 the 9th magnitude in November, 

 drlj near the earth. 

 - Comet.— Th< following is a continuation of 

 M K.n. hem. ivich midnight : 



R.A. Decl I I 



\ . 



1 4 59 



21 13 52 



■ 1 23 8 



14 j 1 32 46 



18 j 1 42 42 



21 52 56 



' 3 -4 



- '4 3 



2 50 N. 02 138 0-060 



1 48 0-21 12 0-.1l.77 



., 5 1 N . 21 >8S 0-0749 



40 



131 



2 8 o • 2 1 



a 40 S. • 



. ' ki [1 to I- of the roi h 01 1 ith magni- 

 tude. 



. I02~l 



Solar-line Disi \nd Relativity. — A 



further contribution to the stud) of sofar-line dis- 

 placements in connection with Einstein's theory of 

 relath it) has I | Evei shed I I lu 



vol. xli.. p. 371). Thirty of the lines 

 composing the c; inogen band [88 were carefull) 

 selected foi observation, and their displacements 



nined '" comparison with th responding 



lines in thi irboi arc. The provisional nflan 



\ alues loi ih. shifts : -004 A al the centi - 



thi disc, and \ at the polar limbs,. There 



appears to bi a curious systematic difference in tv 

 n suits for die north and south rolar limbs, the f. 

 agreeing approximately with the centre ol th. 

 while the l.'iii.i consistent!) showed the much I: 

 displacement of fo-oo8A. The displacements as a 

 whole are larger than those found 1>\ Dr. St. John, inn 

 they are still, on the average, noi much more than 

 half the predicted gravitational effect, whilst for iron 

 lines the shifts are in many cases twice a-- great at 

 the limb as i- required on the relativity hypothesis. 

 In explanation of the limb displacement- Mr. Ever- 

 shed suggests that the effect may possibly be due to 

 the unsymmetrieal shading towards the red .of the 

 majority of the Fraunhofer lines, which would be 

 emphasised at the limb in consequence of the fongei 

 path of the photospheric light through the absorbing 

 vapours. \ large proportion of iron lines have, in 

 fact, been found to be ver) slightly shaded towards 

 the red in the laboratory spectrum. In agreement 

 with Dr. St. John, Mr. Evershed considers his results 

 unfavourable to the theory of relativitv. 



SCIENTIFIC AND PRACTICAL METRIC 

 UNITS. 



\\~l- have received a communication from Dr. John 

 " * Satterley, of the University of Toronto, with 

 reference to Sir Napier Shaw's article on " I nits and 

 Unity " in Nature tor June 27, in which he complains 

 .it "the bewildering arra\ of power- ol i.n" that 

 hamper the C.G.S. system of electro-magnetic units 

 ,unl the practical units ol electricity. Dr. Sat ■ 

 make- the same complaint of other measures based 

 on the metric system, which he admits i- adm 

 for purposes ol scientific measurement, but not for 

 1 ii is simplified and the names of 

 its units are shortened. He cites thi milliwatt as 

 representing a complication so intricate that nobody 

 bm a professional metricist knows what it is. 



lb. communication represents the impossible posi- 

 tion which some teachers of scien. practicall) take 

 up consciously or unconsciously. The introduction of 

 C.G.S. units into scientifii measurement is an accom- 

 plished fact; and ' scientific measurement is to be 

 the headlight ol practical life, it is absurd for the 

 ordinar) sensibli man to be kept in ignorance of the 

 units with which scientific men work. It has 

 remarked in some quarters that Sir Napier Shaw's 

 article should have been addressed to the uninformed 

 and unconverted: that reader- of Nature wen al 



agreed upon the question. But if the agreement is 

 ,,ni\ with the reservation that the organised system ol 

 physical units as il exists is reserved for the 

 circles ol scientific society, while the inch and the 

 -h pvstem are good enough foi the ordina deal- 

 ryday life, it is obvious that thi iractical 

 applications ol sciena in this country must continue 

 to lie 11 ippled as heretofo 



The beginning of Dr. Satterley's complaint is that 

 ■men continually inventing new units— prac- 



tical units iso-called) which arc multiples of the ci 



Who are thi 



