212 



NA TURE 



[July 2, 1908 



the immobilily of the centre of gravity if we know that the 

 direction of the motions of the insects is quite at random ; 

 but tliis is by no moans required. The motion may be 

 preferentially in a horizontal plane or along a determined 

 line, say along the longer axis of the pond, provided only 

 that the motions in any two opposite directions are equally 

 frequent. 



Not only that, even if the cloud, as a whole, is not 

 immovable, we are not necessarily helpless. For, if the 

 insect cloud and the photographer were both on a sailing 

 vessel, circumstances would be the same as on the main- 

 land, though now tlie cloud is in motion. Only, instead 

 of the absolute displacement of the photographic apparatus, 

 we must know the displacement relative to the ship, or 

 rather relative to the insect-cloud. This, then, finally is 

 the real thing wanted. We may obtain the distance of 

 the insect-cloud, or, what comes to the same, the average 

 distance of its members, as soon as we are able to find 

 out the displacement of our point of view with regard to 

 the centre of gravity of the cloud. 



Our case is much the same in the world of the stars. 



We shall be able to determine the average distance of 

 the members of any arbitrary group of stars provided that 

 we can find the motion of the solar system, both in amount 

 and in direction, relative to the centre of gravity of the 

 group. 



Now, astronomical observations such as those which led 

 the elder Herschel to his discovery of the solar motion 

 through space enable us to determine the direction of the 

 sun's motion relative to such groups as the stars of the 

 third, fourth, &c., magnitude. Spectroscopy enables us to 

 determine the amount of that motion. 



We must be able, therefore, to find out the average 

 distance of the stars In these groups. For other groups, 

 such as the stars having an apparent centennial motion 

 of 10", 20", &c., there is a difficulty. Still, however, we 

 have succeeded in overcoming this difficulty by a some- 

 what indirect process, and pressing into service the stars 

 of which the Individual distances are known. This, then, 

 is the upshot of astronomical work on the distances. 



What we knoiv about Star-distance. 



By direct measurement we knoiv the distance of some 

 hundred individual stars. 



For the rest we know the average distance of any fairly 

 numerous group of stars of determinate apparent magni- 

 tude and apparent motion.^ 



The question Is, Can this imper(ect knowledge of the 

 distances be considered as in any wise sufficient for obtain- 

 ing an Insight into the real arrangement of the stars In 

 space? I think it can, and 1 will now try to show in 

 what manner. 



(To he continued.) 



UNIVERSITY ./l.Vn EDUCATION.AL 

 INTELLIGENCE. 



Oxford. — The following is the text of the speeches 

 delivered by Prof. Love in presenting recipients of the 

 degree of D.Sc. honoris causa at the Enca;nla on 

 June 24 ; — 



FuLGENCE Raymond. 



Antequam de hulus viri laudlbus loquar, breviter 

 dl.xerim centum fere abhinc annos celeberrimam medicorum 

 scholam Parlslls exstltlsse, eandem sseculo proximo 

 exeunte, Charcotio famillam ducente, maxima laude 

 floruisse. Charcotio successit Fulgentlus Raymond, 

 magistro disclpulus clarisslmus : quo rem fcllcitcr navante 

 valetudlnarium Salpetrlense, in quo quasi in aliquo orbis 

 terra theatro partes primarias agit, omnium in se ora 

 convertit. Hie exculta; sunt pIuriniK rationes, quae ex eo 



^ At the present moment some objection mi^ht certainly still be made 

 against the generality oT this siatement In fact, the scircity of spectro- 

 scopic data is the cause that, though the deiermination of the solar motion 

 sep.-irately f.)r such groups as the stars of determinate magnitude and proper 

 motion is quite possible, it has not yet been carried through. As a conse- 

 quence, the results used in what follows still rest on the assumption that the 

 centres of gravity of all the groups considered are at rest relative to e.'-.ch 

 other. I'hat this assumption must be probably true follows from the near 

 identity of the dinctlon of the sun's motions, furnished by the several 

 groups. 



pendent quocl ni pra: se feruni qui affirmant posse corpori 

 iC'grolantIs Ipsam mentem meaeri : quo in genere hic 

 noster, dum de cerebri et de medulla: spinalis natura docte 

 luculcntcrque disserit, laudem maxlmain consecutus est. 

 Felicisslmum profeclo amicitia; inter Britanniam et I 

 Galliam rcconciliataj docuinentum duco, quod hi'c vir de 

 medicorum apud Gallos Inslgnissiinorum usu et ratio'nibus 

 magno medicorum nostroruin convcntu Londinii nuper 

 contionatus est. 



Jethbo Justinian Harris Teall. 



DcscrlptionI GeologicEe, impensis publlcis faclenda?, quie 

 saxorum solo Britannico subleclorum naturam, qua vl 

 conflata sint, quo tempore coorta exqulrit, pra;fectus est 

 Jethro Justinianus Harris Teall. Qui vir, quo melius rem 

 tantam conficoret, non in uno tantum genere laudis excelllt : 

 neque enim solum rationes quae latisslme patent animo 

 comprchendere, sed etiam minutisslma quseque et observare 

 et reprcEsentare miro modo potest. His artlbus usus, cum 

 saxorum diverslssimorum compages scrutaretur, omrKa 

 e montlbus vl ignea liquefactis exorta esse cognovit : Idem 

 mutationes quas ha;c saxa patiuntur gravi pondere oppressa 

 subtillssime enarravit. Quo Ingenio, qua peritia in hoc 

 genere usus sit declarat ille liber de Insularum 

 Britannicarum Petrologia conscrlptus, quern aureolum esse 

 ego lure dixcrim. 



James Ward. 



Inter Psychologos nemo clarior est quam Jacobus Ward, 

 qui Psychologlam, cuius scientise proprium sit singulorum. 

 sensus tractare, non ex alia scientia pendere sed sui iuris 

 esse constantpr asseverat : cuius in ore semper est vox ilia 

 " Ego sum. Nihil mihi hoc verlus? " Qui vir ita priorum 

 repertis usus est ut erroribus vitatis longius progrederetur : 

 idem si quid boni usquam invenisset non aspc rnatus novam, 

 quEE latisslme pateret, ratlonem excogitavit et necessi- 

 tudlnem quandam Inter mentein nostram et rerum naturam 

 Intercedere docuit. Psychologiam eliam cum aliis sclenll;c 

 generibus artissime cohsrere monstravit et omnibus qui 

 cognoscendl ratio qu;E sit Investlgant vel hominum moribus 

 student utilissimam esse contendlt. Neque ei satis erat 

 huic scientia; novum quasi fundamentum prsebere, sed 

 muUorum divcrso in genere philosophorum opinloncs re- 

 prehendit : qua; omnia in libro paucos abhinc annos edito 

 pervulgata cum lis qui rerum naturae Investigandae operam 

 dant tum lis qui philosophiae potissimum incumbunt 

 maxime profuerunt. 



Man'Chester. — Lord Morley, Chancellor of the Uni- 

 versity, has nominated the following as recipients of 

 honorary degrees on the occasion of his installation, which 

 has been fixed for Julv c,: — the Right Hon. A. J. Balfour, 

 Mr. E. J. Broadfield (treasurer of the L'niverslty), Mr. 

 .Andrew Carnegie, Lord Courtney of Penwith, Lord Curzon 

 or Kedleston, Sir Ed. Conner, Bart., Dr. k. M. Fairburn 

 (principal of Mansfield College, Oxford), Sir Frank Forbes 

 Adam (chairman of the university council), the Right 

 Hon. R. B. Haldane, Sir H. F. Hl'bbert (chairman of the 

 Lancashire Education Committee), Sir W. H. Houlds- 

 worth, Bart., Prof. Henry Jackson, Sir William Mather, 

 Mr. J. Cosmo Mclvill (donor to the Manchester Museum 

 of the Cosmo-MclvlU herbarium), and Sir Edward Maunde 

 Thompson. In addition, the following honorary degrees 

 win be conferred : — LL.D., Mr. A. J. Evans (keeper of 

 the Ashmolean Museum) and Mr. William Farrer (editor 

 of the " Victoria County History of Lancashire " ; D.Sc, 

 Emeritus Prof. Gamgee. 



Mr. R. E. Slade has been elected to a Gartside travelling 

 scholarship. Dr. Hans Geiger has been re-appointed to 

 the Harling fellowship in physics. 



The Countess of Bective will present the prizes at the 

 Horticultural College, Swanlev, Kent, on Tuesday, July 14. 

 Sir John Cockburn, K.C.M.G., will take the chair at 

 4 p.m. 



We are glad to be able to announce that a petition for 

 a charter for a University of Bristol has been sent to the 

 Privy Council. A concordat is being arrived at between 

 University College, Bristol, and the" Merchant Venturers' 

 Society, which has for many years been Identified with 

 work of technical and secondary education in the city. 

 The most liberal support for the University scheme has 



NO. 2018, VOL. 78] 



