ym. ?i, i§75] 



NATURE 



235 



ordinary telescopic method and by the spectroscopic 

 method described in our former notes. It was found 

 that the difference between the times of observation by 

 these methods itms more tliaji two minutes, contact being 

 observed by the spectroscope first. Now, if the contact 

 had been observed last by the spectroscope, there was an 

 obvious condition of the obsei-vation to which the dis- 

 accord might have been attributed ; but there is now no 

 room for doubt that the sun's extreme edge which we 

 actually see in a telescope differs physically from the part 

 just within it. although there is no difference to the eye — 

 m fact, that it gives a spectrum of bright lines, while the 

 spectrum of the true subjacent sun gives a continuous 

 spectrum with dark lines. Further, the physical differ- 

 ence to which we refer would probably tend to make this 

 stratum variable in thickness and luminosity. Nay, we 

 may already hazard the question whether there is not 

 here a condition which may have something to do with 

 the various times of contact recorded by observers 

 haying object-glasses widely differing either in aper- 

 ture or in the pvgr- or under-correption of the chrpmatic 

 dispersion. 



Another victory achieved by the Italians is the deter- 

 mination of the nature of the atmosphere of Venus. The 

 ring round the planet, which in the former transits as in 

 the present one was visible round Venus both on and off 

 the sun, indicates in the spectroscrope that in that planet, 

 as in our own, the atmosphere is composed to a certain 

 extent of aqueous vapour. 



Mr. Proctor pointed out some time[ago"the great value 

 of photographs taken at the Cnpe of Good Hope in com- 

 bination with those secured at Nertschinsk and Roorkee. 

 We have no information that any photographs were taken 

 gt the Royal Observatory at Cape Town, but a corre- 

 spondent informs us that fourteen successful photographs 

 ?yere taken at Cape Town, two of them showing distinctly 

 the black drop. 



The Times then refers to the final appendices 

 to the " Recueil de Menioires, Rapports et Docu- 

 ments relatifs Ji Fobservation du Passage de Venus 

 sur le Soleil," as enabling us at length to refer to the 

 doings of the Commission appointed by the French 

 Government. The records extend from Februai-y 1S69, 

 when the Government hrst moved in the matter, to a few 

 months ago, when the final instructions on the methods 

 to be adopted to guard the obseryatipns against risk of 

 lo's were issued. 



The first action of the French Government was to ask 

 the Academy of Sciences to consider the places to be 

 occupied, and the number of observers ; the instruments 

 to be used ; the additional researches which might be 

 undertaken by the observers sent to the .Southern Hemi- 

 sphere ; and, finally, whether an Astronomical Congress 

 would not be desirable to bring about a uniform system 

 of observations. 



A strong commission was at once appointed, composed 

 of mathematicians, astronomers, physicists, and chemists, 

 in order that the problem mi^ht be considered in an 

 efficient manner. Strangely enough, the name of M. 

 Leverrier, the distinguished Director of the Paris Obsei-va- 

 tory, does not appear on the commission ; he did not 

 think the observations of the Transit necessary to prove 

 the accuracy of his values of the solar paralla.x. Happily, 

 his voice was overruled. The course taken, as the Times 

 remarks, suggests how desirable some similar procedure 

 here would have been. 



''There are very many points of the greatest inte- 

 rest," the Times continues, " raised by the contents 

 of this large volume to which we should refer did 

 space permit ; from beginning to end it shows how a 

 pation should set itself to work — how all the intellect 

 of a nation can and must be utilised, when a great 

 problem involving many kinds of special knowledge has 

 to be attacked. It is often said that in France science 



is crushed by a dead weight of officialism, and that in 

 England it is free. However true this may be of teaching, 

 there is ample evidence in this volume that, in one branch 

 of research at least, the very opposite of this statement is 

 much nearer the truth, and the painful discussions which 

 some time ago occurred in our own columns and else- 

 where, the ' Appeals to America,' the action of the Board 

 of Visitors of the Greenwich Observatory, and the like, 

 afford a strong argument — if, indeed, one were needed — 

 th.at the growth ot science necessitates that in all future 

 national enterprises of the kind the example of the French 

 and of all the other Governments should be followed. In 

 this way only, in our opinion, can the national scientific 

 honour be upheld, while the officials concerned in carrying 

 out the work would be strengthened in their positions and 

 shielded from a responsibility too great for individuals to 

 bear." 



'NOTES 



The arrangements for securing obscrv.-ilions of the Solar 

 Eclipse of April 6 are progressing most satisfactorily, thanks to 

 the energy of the Royal Society Committee and the varied know- 

 letlge that has been brought to bear upon the various points of 

 .ittack. Lord Salisbury has brought the proposed action of the 

 Royal .Society before the Council of India, and such instniction; 

 have already been telegr.ipheil to India as will probably result in 

 this eclipse being observed with a wealth of obsei-vers and in- 

 s'rumental appliances beyond all precedent. 



Captain Nares, who is to command the English Arctic Ex- 

 pedition, has arrived in London. Commander Markham returned 

 on .Saturday from Dundee, after having entered six good men, 

 tried seal and whale fishers, as ice-quartermasters. Staff-Surgeon 

 Thomas Colan, M.D., of the Unicorn, drill-ship of the Naval 

 Reserve at Dundee, has been selected bvthe Admirably as senior 

 medical officer of the Expedition. With regnnl to the proposed 

 Germ.an Expedition, the desire is, we believe, if the funds can 

 be raised, to form a scheme of co-operation between the two 

 exploring expeditions. Surely our brother Teutons, richer now 

 than ever they were, and whose zeal for knowledge is pro- 

 verbial, will not allow this splendid scheme to be marred for 

 lack of funds. 



The Ivluseum of the Royal College of Surgeons contains a 

 series of casts of the interior of the cranial cavity, representing 

 exactly the form and size of the brain (when covered by its 

 membranes), of men of various races, and of many species of 

 animals. With a view to diffuse the information to be derived 

 from the study of these casts, and believing that many educa- 

 tional institutions will be glad to avail themselves of the oppor- 

 tunity of possessing them, the Council of the College has 

 authorised the issue of copies at the lowest price at which they 

 can be reproduced, which will partly depend upon the number 

 likely to be required. The Conservator of the Museum would 

 like those who desire to possess the whole or part of the series, 

 wliich comprises many rare forms, to communicate with him on 

 the subject. 



At its Si'aiicc of Jan. 11, the Paris Academy elected a corre- 

 sponding member in the section of Mechanics, in place of the late 

 M. Burdin. Three candidates were proposed — M. Broch, the Nor- 

 wegian mathematician, who obtained twenty-four votes ; Prof. 

 Stokes, F.R.S., twenty-one votes ; and M. Calladon, one vote. 

 Thus M. Broch was elected by only three votes over Prof 

 Stokes. 



Mr. .Simon Newcomii, the American astronomer, is now in 

 Paris. He has paid a visit to the Observatory, in order to 

 inquire into the possibility of constructing a large refracting 

 telescope having a lens of one metre in diameter. A sum of 



