i64 



NA TURE 



[December 14, 1893 



following resolution was then adopted: — "That this meeting 

 desires to mark its deep sense of the benefits conferred on man- 

 kind for all time, as well as of the great honour which has 

 accrued to this district, by the scientific work of the late James 

 Prescott Joule, by the erection of a durable memorial of him in 

 Manchester, in the form of a white marble statue." A represen- 

 tative committee was appointed to raise subscriptions to carry 

 the resolution into effect, and the sum of i^26ii was eventually 

 obtained. 



Almost the first act of the committee was to pass a resolution 

 to the effect that the movement should be directed to secure not 

 only a marble statue of Dr. Joule as a companion to that of Dr 

 Dalton, but also a replica in bronze to occupy some public place 

 ill the city. This object was kept in view for some time, but 

 eventually it was thought advisable to relinquish the idea. After 

 abandoning the scheme of raising a bronze replica of the statue, 

 it was decided that the surplus should be handed over to the 

 Literary and Philosophical Society as a nucleus for the institution 

 of a peimanent Joule Memorial Fund, the income of which is to 

 bi employed, as the council of the Society may direct, for the 

 encouragement and promotion of science. 



The unveiling of the Joule statue was performed by Lord 

 Kelvin, in the presence of a large company. The Manchester 

 Guardian gives a full report of the proceedings, and from it we 

 exiract the following remarks made by Lord Kelvin in the course 

 of his address. 



The Literary and Philosophical Society had the distinguished 

 honour of being really the cradle of Joule's work — first as 

 Dakon's home, and afterwards as Joule's life-long scientific 

 harbour. From very early days he kept constantly in touch 

 with that Society. Many of his most important papers were 

 first given to the world there, and during the last years of his 

 life he was an exceedingly regular — it might almost be said a 

 constair- — attendant at the meetings of the Society. The 

 citizens of Manchester did not require to be told what great 

 things this Society in its rather more than a century's existence 

 had done. 1 heir presence in such numbers on that occasion 

 showed how much they appreciated the results of that very 

 effective scientific institution. Now he ought to say something 

 of the electrical, mechanical, and chemical character of Joule's 

 work, although to examine it properly would require the space 

 not of one address, but of a whole course of lectures illustrated 

 by experiments. A great surprise that came out very early in 

 Joule's work was burning without heat — an absolutely novel 

 idea which Joule developed most wonderfully and most magni- 

 ficently by his experiments in the generation of heat in the 

 voltaic battery, which in those days was the only source of 

 electricity on a large scale. Joule was the first to develop the 

 idea, and it came to him not as a bright flash of genius, but as 

 the demonstrated result of years of hard, measuring, calculating 

 work. This was the fundamental idea that pervaded all Joule's 

 v\oik. A lew years later he expanded it in a wonderful way. 

 About 1846, in a joint paper by himself and Scoresby, he 

 brought out ihe wonderful, the truly philosophical, and at the 

 same lime startling idea that when a man or any other animal 

 walked uphill, only a part of the heat or combustion of his 

 fjod was developed, and that it was when the body was 

 quiescent that the chemical attraction between the food and the 

 oxygen dissolved in the blood developed its whole energy in 

 actual animal heat. He showed, further, that the animal body 

 was more economical for fuel than was any steam engine hitherto 

 realised. This was a very far-reaching idea, and seemed to 

 hold out prospects of greatly advancing the efficiency of the 

 steam engine. That promise had not been lost. It was due 

 to Joule, more than to any other individual, that the great im- 

 provement of surface condensation was now universal, although 

 very rarely practised, indeed, before i860 or 1862. Joule, 

 about the year i860, in working upon a little steam engine, 

 applied a surface condenser on an entirely new principle, and 

 in doing so he was led to think out a mode of getting heat out 

 of the steam to be condensed without sending a jet of water 

 ibto it, as on the oM plan. But he (Lord Kelvin) had not yet 

 touched upon Joule's great fundamental discovery, the dis- 

 covery v\ hich was first in everyone's mouth — that of the mechani- 

 cal equivalent of heat. They would understand that it was not 

 merely by achance jnece of measurement that he stumbled on 

 this result, which was afterwards found to be of great value. 

 It was measurement, rigorous experiment and observation, and 

 philosophic thought all round the field of physical science that 

 made this discovery possible. Very early indeed in his work- 



NO. 1259, VOL. 49] 



ing time Joule brought out the mechanical equivalent of heat, and 

 in a paper read at the British Association at Cork in 1843, ^nd 

 afterwards in the Fhiloicphical Magazine, he gave the number 

 " 772." Six years later a second determination gave him the 

 same result, and twenty-five years later he made a third deter- 

 mination, which gave him the final andcoirected result "7 72*56. " 

 In the year 1824 a great theory was originated by a very young 

 man, who died only a few years later — Said Carnot, son of the 

 Kepublican Minister, and uncle of the present President of the 

 French Republic. It was he who made "Carnot's theory" a 

 household word throughout the world of science ; and great as 

 was the French President, much as he had done for his country 

 and the world, in after times his uncle would be always re- 

 membered as one of the most distinguished characteristics 

 attached to that great name. Carnot's theory gave an important 

 fundamental principle regarding the development of nrotive 

 power from heat. Joule's work, on the other hand, so far as 

 the mechanical equivalent was concerned, was the generation 

 of heat by mechanical work. It was quite the middle of the 

 century before Carnot's work began to attract attention ; but 

 Joule was early made acquainted with it, and after fighting a 

 iiitle against it as differing from his own theory, he of all others 

 too'K it up in the most hearty manner. Lord Kelvin went on 

 to say that he could never forget the British Association at 

 Oxford in the year 1847, when in one of the sections he heard 

 a paper read by a very unassuming young man who betrayed 

 no consciousness in his manner that he had a great idea to un- 

 fold. He (Lord Kelvin) was greatly struck with the paper. 

 He at first thought it could not be true because it was different 

 from Carnot's theory, and after the meeting he and the reader 

 of the paper, James Joule, had a long and thoroughly discursive 

 talk on the subject, and he obtained ideas he had never had 

 before, although he thought he too suggested something worthy 

 of Joule's consideration when he told him of Carnot's theory. 

 He had the great pleasure and satisfaction for many years, be- 

 ginning just forty years ago, of making experiments along with 

 Joule, which led to some important rejults in respect to the 

 theory of thermodynamics. This was one of the most valu- 

 able recollections of his life, and was indeed as valuable a 

 recollection as he could conceive in the possession of any man 

 interested in science. Joule's initial work was the very founda- 

 tion of our knowledge of the steam engine and steam power. 

 Taken along with Carnot's work it had given the scientific 

 foundation on which all the great improvements since the year 

 1850 have been worked out, not in a haphazard way, but on a 

 careful philosophical basis. James Walt had anticipated to 

 some degree in his compound engine and his expansive system 

 the benefits now realised, but he was before his time in 

 that respect, and had the complete foundation which 

 Joule's mechanical equivalent and Carnot's theory had 

 since given for the improvement of the steam engine. 

 Might he be allowed. Lord Kelvin added, to congratulate 

 the city of Manchester on its proceedings that day? When 

 the cover was lifted from the statue of Joule, he felt deeply 

 touched at the sight of the face of his old friend. To his mind 

 it was a most admirable likeness, and the ideality of the acces- 

 sory of the little model held in the hand seemed to him most 

 interesting and most striking — he thought he might say poetical. 

 That little model was not one of Joule's first or second, but of 

 his third and greatest apparatus for the determination of the 

 mechanical equivalent of heat — that by which he corrected the 

 British Association's standard ohm, which he proved to be 17 

 per cent, wrong. Regarding that standard a diplomatic corre- 

 spondence was now going on between our Foreign Office and 

 other European Governments with a view to arranging the pre- 

 cise terms of the definition of the ohm, which was really first 

 worked out by Joule. Lord Kelvin further asked to be allowed 

 to congratulate the sculptor on the great beauty and the great 

 success of his work, and added that Manchester now possessed 

 statues both of the man who laid the foundation of the atomic 

 theory in chemistry, and of the man who was the originator of 

 the whole subject of thermodynamics. If the prosperity of 

 Manchester did not depend on chemistry and on the steam 

 engine and thermodynamics, he did not know upon w hat it did 

 depend. The energy and industry of its inhabitants were no 

 doubt essential to its success, but they must ever remember 

 that the material prosperity of the city was as much dependent 

 on philosophic thought as it was upon any material appliance 

 whatever. 



Sir H. E. Roscoe, M.P., in moving a vote of thanks to Lord 



