July 25, 1895] 



NA TURE 



sun, which finally has its centre of motion in a "central " 

 sun. " The evidence of the existence of the central, 

 polar, and equatorial suns is found in certain observed 

 phenomena, hitherto attributed to other causes, but which 

 are in reality due to their presence and influence." 

 Besides the simple enumeration of these phenomena, it 

 is in vain to look for any direct proof of tliis statement. 

 The authors method of removing objections to his theory, 

 one of the principal objects of this book, is, however 

 complicated in detail, extremely simple in principle. It 

 practically consists in calling a motion, or an absence of 

 motion, when it docs not fit in and support his theory, 

 apparent, and when such motion can be explained, or 

 Dr. Pratt considers is explained, ?vw/. Such juggling with 

 phenomena resulting from a combination of revolution 

 and rotation, naturally presents no difficulty to a man 

 who cannot see that a body re\olving in an orbit, and 

 always presenting the same face to the centre of the 

 orbit, rotates once in the period of revolution. But others, 

 taught in a ditTerent and more rigorous school, have great 

 difficulty in apprehending the authors meaning, and fail 

 altogether to appreciate the arguments by which he seeks 

 to support the successive parts of his theoretical system. 

 Neither does Dr. Pratt understand the arguments, nor, 

 as far as we can see, admit the facts, by which the 

 gravitational theory is supported. In the third chapter, 

 the author, in criticising our current ideas of planetary 

 motion, discloses the awkward fact, that he has not the 

 slightest acquaintance with Kepler's laws. He has not 

 taken the trouble to master the first principles of the 

 system he would overthrow, but seems to think himself 

 qualified by inspiration to offer another. His inspira- 

 tion, we fear, is due to a disordered and ill-regulated 

 imagination. 



LETTERS TO THE EDITOR. 



The Editor does not hold himself responsible for opinions ex- 

 pressed by his correspondents. Neither can he undertake 

 to return, or to correspond with the writers of, rejected 

 manuscripts intended for this or any other part of NATURE. 

 No notice is taken of atumymous communications.'\ 



The Physical Properties of Argon. 

 The following iiic.isurements may be of interest in connection 

 with the chemical position of argon. The gas was prepared 

 from atmospheric air with the aid of oxygen and alkali only. 



Weighings at 0° C. upon a large .scale (two litres), and with 

 the apparatus formerly employed for other gases, give as the 

 density of argon (O^ = i6) 



19-940, 



a number in-almost exact agreement with that obtained by Prof 

 Ramsay, working u]ion a relatively small scale and with gas 

 derived by magnesium (Rayleigh and Ramsay, Phil. Trans., 

 1895). 



In spite of its greater density, the refraction (/i ~ i ) of argon is 

 only '961 of that of air : so that if we take for air under standard 

 conditions 11 = I 0002923, then for argon 

 /» = I '000281. 



Terling Place, July 20. Ravi.kigh. 



The Teaching University for London. 



I WAS absent from the country during the University of 

 London Election ; but I may be jiermitted to make a few re- 

 marks on .Sir John Lubljock's letler in the last number of 

 Nature. 



I am afraid he has hardly weighed the very serious con.sc- 

 quences of the action he has taken. They will have to be met 

 as best we may. What I now desire to consider is some of the 

 grounds im which he has attempted to defend it. These them- 

 selves afford matter fur sufiiciently grave reflection. 



(i. ) Sir John states in his letter to Prof. Riicker : " I am not 

 asking that any privilege which they do not at jiresent possess 



NO. 1343, VOL. 52] 



should be conferred on my constituents, but only sujjporting 

 what is now their legal right. . . . This right I know they 

 highly value." This is a most extraordinary statement. What 

 Convocation undoubtedly possesses is the right of veto on any 

 fund.imental change in the constitution of the University. It 

 has been exercised in the past to some eflfect when Convocation 

 summarily rejected the recommendations of the first of the re- 

 cent Commissions. It might have been exerci.sed when Convo- 

 cation assented to the admission of women to the University. 

 But it has never hitherto been exercised except by the personal 

 vote of members attending Convocation who have had the opjior- 

 tunily of hearing in adequate debate the arguments for and 

 against the pro]5osal at issue. What -Sir John jiroposes now is 

 something widely difllerent : a referendum, in fact, in which the 

 decision of Convocation is to be signified " as at a Senatorial 

 election," i.e. by voting papers. In my judgment such a prece- 

 dent, if once established, would utterly destroy the prestige and 

 authority of the meetings of Convocation as at present consti- 

 tuted. To this ]>oint I will return presently. But at any rate I 

 think it will be admitted by all who know anything of the practical 

 working of this body that Sir John's proposal is a pretty revo- 

 lutionarj- change. Mow then are we to reconcile it with his 

 language which I have quoted above. 



(ii.) But .Sir John's action becomes still more extraordinary in 

 the light of the actual recent proceedings of Convocation itself 

 To read his letter it might be thought that we were smarting 

 under a sense of injury and injustice, and that Sir John, as in 

 duty bound, had come chivalrously to the rescue of our oppressed 

 body. Far from this beint; the fact, I think, that in plain 

 language .Sir John has given Convocation the severest slap in 

 the face it has ever received. 



After the report of the first Commission was dead and buried, 

 the second came up in due course for consideration by Convoca- 

 tion, and for the past two years its mind has been occupied with 

 little else. The report might have succumbed to the veto like 

 its predecessor, but it did not. I need not recaiiitulate all that 

 has happened. It is enough to say that though Convocation 

 approached the conclusions of the Commission with a certain 

 timidity or, at any rate, reserve, their substantial acceptance after 

 each successive debate steadily gained ground. 



Finally at the meeting on January 22 of the present year the 

 following resolution was carried : — 



"That Convocation, while desiring to express generally its 

 approval of the jiroposals contained in the Report of the Royal 

 Commission, is of opinion that pi.iwer ought to be given to the 

 Statutory Commission to vary the details of the scheme, and 

 that it ought to be made an instruction to the Commissioners, 

 before framing the statutes and regulations, to confer with duly 

 accredited representatives of the Senate and of Convocation, as 

 to the modifications which may be desirable." 



Now- whatever be the opinion of different sections of Con- 

 vocation on the general merits of the question, I think that we 

 are all agreed as to the latter part of the resolution. ConviKa- 

 tion regards the Report as a possible basis for reconstruction, but 

 declines to pledge itself to all the details. But it is most im- 

 portant to observe, and it was most clearly jiointed out in the 

 debate, that in adoi^ting this resolution Convocation waived its 

 right of veto. In other words it dropped its possible non 

 possuiiius and looke<l to negotiation to attain what it wanted. 



This resolution was followed by a further one, which was its 

 necessary executive corollarj'. I may be permitted to extract 

 the whole from the minutes, as it is significant to observe that it 

 was moved and seconded by a representative of either side. 



" On the motion of S. P. Thompson, D.Sc, B..\., seconded 

 by T. B. Napier, LL.D. Resolved:— 



" ( I ) That a Special Committee of nine members, including the 

 Chairman of Convocation, be nominated to prepare for presenta- 

 tion to the Statutory Commission, when appointed, a memo- 

 randum of points in the Scheme of the Royal Commission in 

 which modification is desirable, and with power to confer with 

 such said Statutory Con-mission, and with any Committee of the 

 Senate. 



"(2) That this Special Committee consist of the following 

 Members : — The Chairman of Convocation, Dr. .\llehin. Mr. 

 Bompas, .Mr. Stanley Boyd, Dr. Cave, Mr. Cozens- Hardy, Mr. 

 Thisellon-Dyer. Dr. Napier, Dr. S. P. Thompson." 



Now I JHU it to .Sir John, who, tlu>ugh I am glad to say not" an 

 old," is certainly an experienced " parliamentary hand," whether 

 the action he has taken is exactly courteous to Convocation in 

 general or to its formally constituted Committee in particular. 



