February 23, 1905J 



NA TURE 



401 



the observations extend over nearly a month, and M. Fayet 

 has made another research regarding this comet's orbit, 

 obtaining the following set of elements as his result ; — 

 T = 1905 Jan. 16 65370 (IVI.T. Paris) 

 Jj = 76' 41' 34" '49) 

 i = 30° 31' 5«"7S l-igoS'o 

 =« = 352° 13' 58"-98J 

 log,/ =0-145175 

 log e = 9-792206 

 M = 5o3"'932 

 These elements give a close agreement .with the places 

 determined by independent observations, and indicate that 

 Borrelly's 1904 comet is, really, of the short-period type, 

 completing its orbital revolution in about seven years, 

 instead of six years as given by the previous elements 

 {Comptes rendui, No. 5, 1905). 



The Sun's Rotation. — During the years 1899, 1900, and 

 1901 Prof. N. C. Dun^r made a further series of observ- 

 ations of the rotation velocity of the sun at different helio- 

 centric latitudes. Combining the results with those 

 obtained by him during a similar research prosecuted in 

 the years 18S7-1SS9, and now corrected, he found the values 

 given in the following table : — 



0-4 ... +2'05 



150 ... -t-i-97 



30-1 ... +1-70 



450 .. -1-1-27 



60-0 ... +0-81 



750 ... +0-39 



183 

 180 



184 

 iSi 

 1S3 

 184 



14770 ... 1477 



13989 ... 14-48 



12-072 ... 1395 



9018 ... 12-75 



5-752 ... 11-50 



2-769 ... 1070 



wherein if> = the heliocentric latitude, v — the rotational 

 velocity of the sun's edge, n = the number of observations, 

 and i = the daily rotation angle ly.\sUonomische Nach- 

 richten. No. 3994). 



Second.'Vry Sh.^dow on Saturn's Rings. — During a 

 series of observations of Saturn made at Aosta (Italy) in 

 October, November, and December, 1904, Signers M. 

 Amann and CI. Rozet observed a secondary shadow, other 

 than that of the planet, projected on to the illuminated 

 surface of the rings. First seen on October 20, this 

 shadow was thinner and much less accentuated than that 

 of the planet, whilst its curvature was in the opposite sense 

 to that of the latter body. From October 20 to November 

 15, despite the fact that numerous opportunities of 

 observing it occurred, the shadow was not seen, but from 

 the latter date until the end of December it was shown on 

 twenty-six drawings of the system. On seven drawings made 

 between December 22 and 27, the shadow appeared bifur- 

 cated where it traversed the inner ring, and on November 

 28 and 2q a third line of shadow, narrower and feebler 

 than the preceding and much further from the planet, was 

 seen (Comptes rendus. No. 5, 1905). 



Observations of the Zodiacal Light. — During a so- 

 journ on the summit of Mont Blanc on September 21 

 and 22, 1904, M. A. Hansky made a number of observ- 

 ations of the Zodiacal Light, and found that its form was 

 that of a spherical triangle having its apex near to the 

 ecliptic. At 3h. 40m. (M.T. Paris) the altitude of the apex 

 was 52°, the length of the triangle, reckoned from the 

 centre of the sun, was 80°, and its breadth was, at the 

 horizon, 25°, and in the plane of the sun's axis 30°. The 

 latitude of the apex was +2°, and three zones were distin- 

 guishable in the light. The first of these had the form of 

 a spherical triangle and was very feeble, the second was 

 more parabolic, whilst the form of the third was a parabola. 



In his paper, published in the Comptes rendus (No. 6, 

 1905), M. Hanskf indicates the points of resemblance be- 

 tween this phenomenon and the corona, and makes a 

 number of speculations as to the true nature of the light. 

 He concludes by saying that he believes it to be an elec- 

 trical phenomenon of the same type as the corona, and 

 that it is, probably, simply a prolongation of the coronal 

 streamers. 



Permanent Numbers for the IVTinor Planets discovered 

 during 1904. — In No. 3994 of the Astronomische Nach- 

 richten, the permanent numbers allotted to the minor 

 planets discovered during 1904 are given. The list con- 



NO. 1843, "^OL. 71] 



tains the numbers 522 to 548, inclusive, thereby showing the 

 number discovered during last year to be twenty-seven. The 

 provisional designation, the name of the discoverer, the 

 date of discovery, and the authority for the orbit are also 

 given for each planet. A number of notes explain the 

 absence, for various reasons, of several bodies, to which 

 provisional designations were allotted, from the final list. 



STUDIES IN EUGENICS. 

 A T a meeting of the Sociological Society on February 14 

 -^^ Mr. Francis Gallon communicated two papers: — 

 (i) restrictions in marriage, and (2) studies in national 

 eugenics. 



In the first paper he remarked that marriage, as one of 

 the soiial agencies that influenced the racial qualities of 

 future generations, came within the purview of eugenics. 

 It belonged to the practical policy arising out of eugenic 

 science, to promote such choice in marriage as should 

 tend to the reproduction of the higher types of individual. 

 Anthropological investigation had shown marriage to be 

 one of the most modifiable of social institutions. Hence 

 the assumption was warrantable that with the gradual 

 incorporation of eugenic conceptions in the social ideal, 

 there would proceed a concomitant change in the customs 

 and conventions affecting marriage. The paper then pro- 

 ceeded to illustrate by actual examples the modifiability 

 of marriage customs. In one or other of its many forms 

 polygamy was now permitted — by religion, customs and 

 law — to at least one-half of the population of the world, 

 though its practice might be restricted, on account of cost, 

 domestic peace, and the insufficiency of females. In 

 Christian nations the prohibition of polygamy, under severe 

 penalties, by civil and ecclesiastical law had been due, not 

 to any natural instinct against the practice, but to con- 

 sideration of social well-being. Hence it might be inferred 

 that equally strict limitations of freedom of marriage 

 might, under the pressure of worthy motives, be hereafter 

 enacted for eugenic and other purposes. Endogamy, or 

 the custom of marrying exclusively within one's own tribe 

 or caste, had been sanctioned by religion and enforced by 

 law in all parts of the world, but chiefly in long-settled 

 nations, where there was wealth to bequeath and where 

 neighbouring communities professed different creeds. 

 Endogamous systems of marriage rested on customs deter- 

 mined bv a certain religious view of family property and 

 family descent. Eugenics dealt with what was more valu- 

 able than money or lands, namely, with natural inherit- 

 ance of high character, capable brains, fine physique and 

 vigour, in short, with all that was most desirable for a 

 family to possess. It aimed at the evolution and preser- 

 vation of high races, and it well deserved to be strictly 

 enforced. In every society there existed conventional re- 

 strictions of the nature of " taboo," though not necessarily 

 called by that name. If non-eugenic unions were pro- 

 hibited by such taboos, none would take place. Marriage 

 selection was very largely conditioned by motives based on 

 religious and social convention. Persons who were born 

 under the various marriage systems lived under such rules 

 without any objection. They were unconscious of their 

 restriction. 



Under the heading " Studies in National Eugenics," Mr. 

 Galton communicated what he described as " an un- 

 authorised programme " of what he conceived to be the 

 duties of the Francis Galton research fellowship in 

 national eugenics. The topics to be considered he classified 

 under the following headings : — (i) Estimation of the aver- 

 age quality of the offspring of married couples from their 

 personal and ancestral data. This included questions of 

 fertilitv, and the determination of the probable error of 

 the estimate according to the data employed. (2) Effects 

 of action bv the State and by public institutions. (3) Other 

 influences that further or restrain particular classes of 

 marriage. (4) Heredity. The facts, after being collected, 

 should be discussed, for improving our knowledge of the 

 laws both of actuarial and of physiological heredity, the 

 recent methods of advanced statistics being of course used. 

 (5) Bibliographical compilations. (6) Extension of eugenic 

 studies by wider cooperation. (7) Certificates. With re- 

 gard to the last named, he said that in some future time, 

 dependent on circumstances, he looked forward to a suit- 



