3o6 



NA TURE 



[January 30, 1908 



connection with the Beddoes brought him the friendship 

 of the Edgeworths, and it is amusing to trace how the 

 good-humoured patronage of the gifted Maria quickly 

 passed into amazement and ended in awe as her acquaint- 

 ance with him ripened. Living in Bristol, he was al 

 once brought into that remarlcable literary coterie which 

 distinguished that city at the close of the eighteenth 

 century. Southey spoke of him as a miraculous young 

 man, whose talents he could only wonder at. Cottle, the 

 publisher, on one occasion said to Coleridge, " You have 

 doubtless seen a great many of what are called the cleverest 

 men — how do you estimate Davy in comparison with 

 these?" Mr. Coleridge's reply was strong and expressive. 

 " Why, Davy can eat them all! There is an energy, an 

 elasticity, in his mind which enables him to seize on and 

 analyse all questions, pushing them to their legitimate 

 consequences. Every subject in Davy's mind has the prin- 

 ciple of vitality. Living thoughts spring up like turf 

 under his feet." 



Davy's experimental work on " the pleasure-giving air " 

 had made him known to the Watts and the Wedgwoods. 

 Priestley, then in exile, and Hope, of Edinburgh, were 

 greatly impressed with the philosophical acumen of the 

 author of phosoxygen, and he had a powerful friend in 

 his own countyman Davies Gilbert, who succeeded him in 

 the presidential chair of the Royal Society. We need be 

 in no doubt, therefore, as to the influences which con- 

 spired to bring Davy into what he termed " the great hot- 

 bed of human power called London." 



The mention of Davy's first course of lectures in this 

 institution brings me at once to the proper subject of this 

 discourse. 



The first year of the last century is memorable for the 

 invention of the voltaic battery and for its immediate 

 application by Nicholson and Carlisle in this country to 

 the electrolytic decomposition of water. 



Davy himself has said : — " The voltaic battery was an 

 alarm bell to experimenters in every part of Europe ; and 

 it served no less for demonstrating new properties in 

 electricity, and for establishing the laws of this science, 

 than as an instrument of discovery in other branches of 

 knowledge ; exhibiting relations between subjects before 

 apparently without connection, and serving as a bond of 

 unity between chemical .ind physical philosophy." 



We owe it to Sir Joseph Banks that Volta's great 

 discovery was first made known to English men of science, 

 and the study of the phenomena o' galvanic electricity was 

 at once entered upon by a score of experimenters in this 

 country. Among them was Davy. Even before he left 

 Bristol he was hard at work on the subject, sending the 

 results of his observations to Nicholson's Journal in a 

 series _ of short papers. He resumed his inquiries 

 immediately on his arrival in London, and was doubtless 

 w«ll prepared, therefore, for his opening course of lectures. 



In i8oi he sent his first communication to the Royal 

 Society on " An Account of some Galvanic Combinations 

 forrned by the Arrangement of Single Metallic Plates and 

 Fluids, Analogous to the New Galvanic Apparatus of Mr. 

 Volta." Although the work was continually interrupted 

 by requests made to him by the managers to carry out 

 their own ideas of facilitating the means of procuring the 

 comforts and conveniences of life, he never lost sight of 

 the subject of voltaic electricity, and in spite of innumer- 

 able distractions due to the 'precarious position of the 

 institution, he gradually accumulated the material out of 

 which grew his first Bakerian lecture, " On some 

 Chemical .Agencies of Electricity." read before the Rova! 

 Society on November 20, 1806. I have ventured elsewhere 

 to express my opinion of this paper. In my judgment it 

 constitutes, in reality, Davy's greatest claim as a philo- 

 sopher to our admiration and gratitude, for in it he, for 

 the first time, succeeded in unravelling the fundamental 

 laws of electrochemistry, and thereby imported a new 

 order of conceptions, altogether unlocked for and un- 

 dreamt of, into science. 



I am only at the moment concerned with this memoir 

 m its relation to the discovery of which to-night we 

 celebrate the centenary. The isoKation of the met.nis of 

 the alkalis was unquestionably an achievement of the 

 highest brilliancy, ' and as such appeals strongly to the 

 popular imagination. But it was only the necessary and 



NO. IQ96, VOL. 77] 



consequential link in a chain of discovery which, had Davy 

 neglected to make it, would have been immediately forged 

 by another. 



The publication of Davy's first Bakerian lecture pro- 

 duced a great sensation, both at home and abroad. 

 Berzelius, years afterwards, spoke of it as one of the most 

 remarkable memoirs that had ever enriched the theory 

 of chemistry. Very significant, too, of the impression it 

 made on the world of science was the action of the French 

 Institute. Bonaparte, then First Consul, had announced 

 his intention of founding a medal " for the best experi- 

 ment which should be made in the course of each vear 

 on the galvanic fluid," and a committee of the institute, 

 consisting of Laplace, Halle, Coulomb, Hauy, and Biot, 

 was appointed to consider the best means of giving effect 

 to the wishes of the First Consul. To the young man, 

 with the little brown head, like a boy (as Lady Brownrigg 

 described him), now twenty-eight years of age, was 

 awarded the medal. All the institute got from the founder 

 of the medal was what Maria Edge worth termed " a 

 rating all round in imperial Billingsgate." There was no 

 entente cordiale in those days; indeed, the feeling of 

 animosity was intense. Of course, there were persons 

 who said that patriotism should forbid the acceptance of 

 the award. Davy's own view was more sensible and 

 politic: — " Some people," he said to his friend Poole, 

 " say I ought not to accept this prize ; and there have 

 been foolish paragraphs in the papers to that effect ; but 

 if the two countries or Governments are at war, the men 

 of science are not. That would, indeed, be a civil war of 

 the worst description ; we should rather, through the 

 instrumentality of men of science, soften the asperities of 

 national hostility." 



Thanks to the kindness of Dr. Humphry Davy Rolleston, 

 the grandson of Dr. John Davy, the brother of Sir 

 Humphry, who has also been so good as to lend me this 

 admirable bust of the great chemist by Chantrey, and this 

 charming portrait by Jackson, I am able to show you 

 this evening this historically interesting medal. 



What Davy looked like at this period of his life may 

 be seen from the picture I now project upon the screen. 

 It is a reproduction of the large portrait which hangs in 

 the vestibule, and which the institution owes to the 

 thoughtful kindness of the late Mr. Graham Young. 



As the applications of voltaic electricity seemed in 1806 

 to have no immediate bearing on the comforts and con- 

 veniences of life, Davy, during the greater part of the 

 following year, was required to direct his attention to other 

 matters. But in the late summer of 1807 he was able 

 to resume his work with the voltaic battery, and he 

 commenced to study its .action on the alkalis. 



That the alkalis — potash and soda — would turn out to 

 be compound substances was not an unfamiliar idea at 

 the time, and it is significant that almost immediately 

 after Nicholson and Carlisle had resolved w-ater into its 

 elements by the action of voltaic electricity, Henry, of 

 Manchester, the friend and collaborator of Dalton, should 

 have made the attempt to apply the same agency to the 

 separation of the presumed metallic principle of potash. 

 The conception that what the older chemists called 

 " earths " might be made to yield metals was at least 

 as old as the time of Boyle, and probably dates back from 

 the earliest days of alchemy. The relation of the earths 

 to the metals was part of the doctrine of Becher and 

 Stahl ; it was no less a part of the antiphlogistic doctrine 

 of Lavoisier, although the points of view were diametric- 

 ally opoosed. Neumann attempted to obtain a metal from 

 lime, Bergman considered that baryta was, like lime, a 

 metallic calx, and Baron that alumina contained a metal. 

 From their many analogies to these substances it was not 

 unreasonable, therefore, to surmise that potash and soda 

 might also contain metallic principles. 



I have elsewhere pointed out that there is some evidence 

 that whilst at Bristol Davy had already attacked the 

 problem of the resolution of the alkalis by me.ins of voltaic 

 electricity. What precise idea he had in aenin attacking 

 it. or what expectation he had of a definite result, is 

 difficult to determine. In one of his lectures on electro- 

 chemical science, delivered some time subsequently, he 

 said he had a suspicion at the time that potash might 

 turn out to be " phosphorus or sulphur united to nitrogen," 



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