62 



NA TURE 



[March 17, 1910 



some of the colleges of Oxford and Cambridge, to 

 rookeries of the worst description. The University 

 had either to await the amelioration of these sur- 

 roundings, which came later, or leave its beautiful 

 old quadrangles to seek a new home where no 

 such environment existed. Since its establishment 

 on GilmorehiU, it has found the growth of engineer- 

 ing science react enormously on the study of 

 natural philosophy; and now a great new Natural 

 Philosophy Institute and the James Watt Engineer- 

 ing Labo'ratories exist together, within hearing of 

 the clang of hammers in the great practical labora- 

 tories of the Clyde, with which, by their students 

 and the practical problems which continually arise for 

 solution, they are kept constantly in touch. The 

 opening of this institute and of other new build- 

 ings by the Prince of Wales on April 23, 1907, was 

 the last public ceremony at which Lord Kelvin 

 presided as Chancellor of the University. The confer- 

 ring of honorary degrees on the Prince and Princess, 

 which was only one of the incidents of the ceremony, 

 is mentioned bv Prof. Thompson; but the real 

 occasion of the visit, directly connected though it was 

 with Lord Kelvin's own work in the University, has 

 somehow escaped his attention. 



A full account is given of Lord Kelvin's under- 

 graduate career at Cambridge, and of the visit to 

 Paris which followed it. By that visit, which he 

 made at the suggestion of his father, and with 

 introductions obtained by him, the young mathe- 

 matician benefited in many ways. He made the 

 acquaintance of Cauchy, Chasles, Liouville, Sturm, 

 'and Regnault, and besides studying French— and the 

 cornopean— under Parisian teachers, devoted himself 

 to practical physical work under Regnault, who was 

 perhaps the greatest experimentalist of the century. 

 He received no systematic instruction in experiment- 

 ing—there was then no provision for such instruction, 

 nor for long after was any provided at any university— 

 but he was present to work the air-pump or to hold 

 a tube, or to stir a calorimeter when told to do so, 

 and thus learned something of the technique of 

 physical manipulation. It must be admitted that he 

 never became himself an expert at such work ; and 

 his natural impetuosity in later years, when the irons 

 he kept in the fire were almost innumerable, made 

 his presence in the laboratory a source of perturba- 

 tions which seriouslv interfered with the systematic 

 progress of research. Thus there was just a shade 

 of truth in the legend— written on the blackboard by 

 a laboratory student when the knighthood after the 

 laying of the 1866 Atlantic cable was announced— 

 *'The (k)night cometh when no man can work"! 



The story of his election to the chair of natural 

 philosophy 'in 1846 is told in detail, and it is inter- 

 esting to read the principal testimonials presented by 

 Thomson, which have been printed from a com- 

 plete set in the possession of Dr. Hutchison, of 

 Glasgow. There can be no doubt that he had 

 already impressed all the scientific men whom he 

 had met with his extraordinary ability and promise, 

 and all who support his candidature— including 

 MM. Regnault and Liouville, and Hopkins, Fuller, 

 Leslie Ellis, and De Morgan, predict for him a dis- 

 NO. 2107, VOL. 83] 



tinguished future as an investigator. In an appendix 

 to chapter v. (the subject of which is "The Young 

 Processor") is printed the famous introductory ad- 

 dress which was annually brought out to be read at 

 the first meeting of the natural philosophy class for 

 the session, but which was invariably departed from 

 within the first three or four minutes, and laid aside 

 to be taken up again only after the lapse of another 

 year. It was a matter for regret that it was not read 

 through each year— it was read through in 1846, in 

 much less than the allotted time, and Thomson was 

 so disconcerted that he could find nothing to go on 

 with !— for its language is simple and yet dignified, 

 and well fitted to impress the minds of youthful 

 students beginning the study of natural science. In 

 this address he distinguishes between what he calls 

 "mental history" and "mental philosophy," and be- 

 tween "natural history" aind "natural philosophy." 

 He says that 



"What may bv the analogy of terms be called men\a\ 

 historx that is to say, a combination of personal ex- 

 perience and a knowledge of men and of manners, 

 with the studv of politics and history, leads us tc 

 reason upon the abstract properties of mind, and t( 

 investigate that svstem of general laws on \vhich 

 mental philosophy is founded. So in the_ study o 

 external nature, the first stage is the description am 

 classification of facts observed with reference to thj 

 various kinds of matter of which the properties atl 

 to be investigated ; and this is the legitimate work d 

 Natural History. The establishment of general law 

 in anv province of the material world, by inductioi 

 from the facts collected in natural history, may witl 

 like propriety be called Natural Phtlosophy." 



Thus the observations, and their comparison an 



classification, which led to Kepler's laws, beloni 



to the "natural history" of celestial mechanics 



Newton's deductions from Kepler's laws, and th 



theory of universal gravitation, which accour 



for all the motions of the planets, belong to th 



"natural philosophy" of the subject. The fund: 



mental subject of natural philosophy is said to I 



dynamics, or the science of force, and it is interestin 



to find the importance of this foundation insisted upc 



for all the principal divisions of physics. Referring 



three of these— heat, electricity and magnetism, 1 



says :— j 



"Our knowledge of these branches of the science , 



not so far advanced as to enable us to reduce all tl 



various phenomena to a few simple laws from whic, 



as in mechanics, bv means of mathematical reasonin, 



everv particular result may be obtained ; but obsery| 



tion'and experiment are the principal means by whi 



our knowledge in this department may be enlargt| 



Hence what is called the experimental or physi., 



course includes these three subjects; while the m(| 



perfect sciences of mechanics [here he mea 



"dynamics"; "mechanics" he always defined as 



science of machines] and optics, being really mat) 



matical subjects, form a distinct division of the stud 



prescribed by the University for the complete couj 



of Natural Philosophy." j 



Thomson does not seem to have dwelt on 

 deductive processes of mathematical physics in ^ 

 address, though these are quite as important as^ 

 induction with which they must be combined. J 

 deductive process bv which Adams and Levcrrier m 



