Dec. 5, 1889] 



NATURE 



"7 



which has just been so cordially drunk by you. For reasons 

 which my brother medallists at least can fully appreciate, no one 

 feels that regret more keenly than I do. I may confess that it 

 was with a feeling akin to astonishment that I received through 

 a good-natured friend the intimation that the Council of the 

 Society had seen fit to honour such chemical work as I had been 

 able to do by the signal recommendation of the award of a 

 Royal Medal ; but that feeling culminated into something like 

 consternation when you, Sir, informed me of your wish that I 

 should reply, in the absence of the Copley Medallist, to the 

 toast with which you have connected my name ; and I began 

 to realize the full force of the truth that there are occasions when 

 it is more blessed to give than to receive. Dr. Salmon's absence, 

 however, enables me to attempt to give expression to the feeling 

 of satisfaction and pleasure with which, I am informed, the 

 mathematical world regards this year's award of the Copley 

 Medal. The worker in the field of pure mathematics appeals 

 for recognition to a very select few ; his work is, indeed, caviare 

 to the general ; his are not the triumphs which appeal to the 

 popular fancy or which strike the popular imagination. If he 

 labours for fame, he must be content to wait with the certain 

 knowledge that, if his work be good and true, it will at length 

 meet with the recognition it merits from a tribunal which is un- 

 moved by prejudice and is insensible to the forces of fashion or 

 faction. For nearly half a century Dr. Salmon has so worked, 

 and to-day he receives his reward at the hands of the highest 

 scientific tribunal in the world by the award to him of the most 

 precious gift which it is in the power of that tribunal to bestow. 

 The other medallists. Dr. Gaskell and Dr. Perkin, are happily 

 with us to-night to receive the congratulations of their fellow- 

 workers in science, and to be witnesses of the cordiality with 

 which their health has been drunk by you. But I cannot forego 

 the opportunity of saying also, in their case, how entirely your 

 awards have been appreciated by the great body of scientific 

 opinion, both within and without the Royal Society. To be 

 praised by men who are themselves praised is, we all know, the 

 very highest form of approbation that a man can enjoy, and 

 such, to my knowledge, is the happy lot of the gentlemen whom 

 you have been pleased to honour to-night. It is, h >wever, one 

 of the penalties to a man who is in the position in which I now 

 find myself, and who does not pretend to be an Admirable 

 Crichton, that he is unable from his own knowledge, or rather 

 from the imperfecti m of it, to do adequate justice to the claims 

 which such men have upon your regard. Dr. Gaskell's work is so 

 entirely outside my own province that it would be in the highest 

 decree presumptuous on my part to offer you any expression of 

 my own opinion as to its merits. Of my colleague and fellow- 

 worker, Dr. Perkin, to whom your Council has awarded the 

 Davy Medal, I trust I may be allowed to speak with greater 

 freedom, because in his case I am more or less upon my own 

 ground, and am talking about matters which are within my own 

 knowledge. It is exactly ten years since that Dr. Perkin was 

 placed by your Council in the position in which I find myself 

 to-day. In awarding him a Royal Medal on that occasion, our 

 former President, the late Mr. Spottiswoode, took the oppor- 

 tunity to say that Dr. Perkin had then been, during more than 

 twenty years, one of the most industrious and successful workers 

 in organic chemistry, and he added that it was seldom that an 

 investigator had extended his researches over so wide a range as 

 was the case with Dr. Perkin, whose work had always com- 

 manded the admiration of chemists for its accuracy and com- 

 pleteness, and for the originality of its conception. There is 

 not a chemist here present who will not cordially re-echo these 

 words. Dr. Perkin is, no doubt, known to you all as the 

 originator of one of the most important branches of modern 

 chemical industry — that of the manufacture of colouring matters 

 from coal-tar derivatives — an industry which has acquired almost 

 colossal proportions, and which has effected a complete revolu- 

 tion in the tinctorial arts. I say it with bated breath to you. 

 Sir, as the member for the University of Cambridge, but we all 

 remember the famous saying of Swift as to the value to man- 

 kind of the whole race of politicians put together when com- 

 pared with that man who has made two blades of grass to grow 

 where only one blade grew before. I do not know that Dr. 

 Perkin has achieved that feat, but I claim for him that he has done 

 even more than this, for he has succeeded in demolishing 

 an entire agricultural industry. By his researches he has shown 

 us that we have practically at our own doors, or at least in our 

 own coal-pits, all the richness and beauty of c )lour which were 

 formerly only to be obtained from the madder fields of Avignon 



and the Levant. A beneficent fortune, we are glad to know, 

 has not been unmindful of Dr. Perkin's success in thus enriching 

 the world, and she has endowed him with a share of that material 

 benefit which his skill and genius as an investigator has conferred 

 upon us all. That competency, and the well-earned leisure which 

 has sprung from it, Dr. Perkin has dedicated, with a directness 

 and singleness of purpose which merits our warmest appreciation, 

 to the service of science. Nothing, I think, more clearly in- 

 dicates the truly scientific character of his mind, and his love of 

 science for its own sake, than that he should, whilst compara- 

 tively a young man, have turned aside from the pursuit of the 

 great wealth which all his friends thought would ultimately be 

 within his grasp in order that he might follow, undisturbed, his 

 innate desire for pure scientific research. The ten years which 

 have elapsed since our late President alluded in such character- 

 istically graceful terms to Dr. Perkin's labours in the domains of 

 pure and applied chemistry have been rich in scientific achieve- 

 ment, and they have now culminated in that laborious series of 

 researches on one of the most abstruse points of physical 

 chemistry which has been so fittingly rewarded by you by the 

 gift of the Davy medal. I have already alluded to the 

 feeling with which I received the intimation from my good- 

 natured friend that the Council of the Royal Society had beerk 

 pleased to confer upon me a distinction which is my sole excuse 

 for trespassing upon your indulgence to-night. I will only again 

 refer to that feeling to say that in deference to the express wish, 

 of my di-tinguished friend I am doing my best to get over it. I 

 am bound to add that my friend has himself supplied a reason 

 which in some measure serves to explain the circumstance^ 

 Among the pieces of work which the Council have thought 

 worthy of notice was a redetermination of the atomic weight of 

 gold made in conjunction with Mr. Arthur Laurie. I shall not 

 trouble you with the reasons which made that redetermination seem 

 specially desirable, but that it was desirable will be evident from 

 the fact that no fewer than three independent investigations were 

 in progress at the same time in Germany, England, and America. 

 All the results have now been published, and they are, I think, 

 in very fair accord. But my distinguished friend, whose good- 

 nature is only equalled by his candour, has reminded me that 

 there is a discrepancy of a remote decimal place or so in our 

 several values for the atomic weight, and, in default of any 

 other probable hypothesis, it had occurred to him that the real 

 motive of the Council in making the award was to give me 

 both the hint and the opportunity to clear up the disparity. 

 The Gold Medal, he pointed out, would afford an ample sup- 

 ply of the material on which to base a new determination, 

 and the Silver Medal would come in handy for the pre- 

 paration of the necessary standard solutions. This seemed 

 to me to put the whole matter in a new light, but, on. 

 turning to the official intimation of the award forwarded 

 to me by Dr. Foster, and then to a friendly letter which 

 the President has been so good as to send me, I have not 

 gathered that this intention was ever in the mind of the Council, 

 and until I receive a further official intimation that such was the 

 case, I mean to do my best to preserve intact the counterfeit 

 presentment of the gracious lady which adorns the medals. 

 There is just one other matter connected with my work to which,, 

 with your permission, I would allude. Reference was made in 

 the terms of the award to a series of researches on fluorine 

 compounds on which I have been engaged for some years past. 

 I wish to mention, and I do so with a very special, 

 pleasure, that much of this work has been carried out 

 in cooperation with some of my senior students at the 

 Normal School of Science. This work has been at all 

 times difficult, often disagreeable, and occasionally dangerous, 

 and I am glad to seize this opportunity of testifying to the zeal, 

 assiduity, and, I may add, courage, which my collaborateurs have 

 shown in the progress of the investigations. It is a further 

 satisfaction to me to add that the qualities thus evoked and the 

 training thus ac quired have been of material benefit to them in. 

 their professional advancement, and I can wish them no greater 

 good fortune than that it may be their lot in time to come to 

 occupy my place here, and to be received by you with that in- 

 dulgence which you have extended to me to-night. 



A NEW METHOD OF PREPARING FLUORINE 



A NEW method of preparing fluorine has been discovered by M. 

 •^"^ Moissan. This discovery is the outcome of the success which 

 has attended M. Moisian's effjrts to prepare anhydrous fluorider 



