6io 



NA TURE 



{Oct. 



5» 



of abuse is meant to euphemistically imply all these 

 things. If so, it is a foolish euphemism. 



There are certain notable theorists who are so eminent 

 that no one is willing to stultify himself by abusing them ; 

 and inasmuch as the superabundant energy of some of 

 these men often leads them occasionally out of their 

 main pursuits into alien fields of activity, wherein never- 

 theless they frequently shine as the equals or superiors 

 of smaller men whose life-work lies in the same fields, 

 it is becoming customary to ingeniously attempt to 

 exclude them from the class it is wished to denounce, 

 and to include them in the circle wherein they are 

 comparatively amateurs or dabblers. 



At the recent meeting of the British Association the 

 old joke was repeated about claiming Sir William Thom- 

 son as an electrical engineer instead of a physicist and 

 mathematician. This is all very well as a joke, but the 

 British public is too apt to take these things in sober 

 earnest. The range of activity of a pre-eminently great 

 man is frequently not a narrow one, and he is extremely 

 likely to shine in whatever he takes up, even if it be only as 

 a pastime, or as relief from more serious work. Sir Isaac 

 Newton made an excellent Master of the Mint. Perhaps 

 therefore, in his day, City men claimed him as essentially 

 one of themselves. Sir William Thomson has amused him- 

 self with navigation, as well as with electrical engineering. 



This outcry against theory is becoming absurd. It 

 used to be confined to the conclusions of mathematics. 

 It is indeed still rampant there, but it is being ex- 

 tended also to conclusions deduced in the laboratory. 

 Everything done in the laboratory or the study is 

 looked at with suspicion. The right place to study the 

 laws of steam-engines is on a locomotive. The right 

 place to study marine engineering is in the hold of a 

 steamship. The only place to study lightning is in a 

 thunderstorm. 



Give out these plausible fallacies with a certain unction 

 to a British audience, and you will evoke "loud ap- 

 plause." It is so easy to evoke loud applause by talking 

 pernicious but plausible nonsense. Your British audience 

 hates to think, and likes to have its stupidity tickled by 

 some after-dinner sentiment, which makes it feel that, 

 after all, no one really knows anything about anything ; 

 that whoever professes to understand a subject theoretic- 

 ally is . ipso facto a quack ; and that the only difference 

 between itself and everybody else is that some people 

 cloak their ignorance under a show of learning and 

 mathematical formulae. These humbugging theorists 

 may therefore be cheaply derided. " There is a lot of 

 arrant humbug stowed away now and then under a mathe- 

 matical cloak," said a technical paper the other day. 



And what of the "practical" man? Any man who 

 talks sense and goes to the bottom of things, so as to 

 really understand and to be able to explain what he 

 means and how things are, is essentially a practical man. 

 One class has no right to monopolize this adjective. A 

 mathematician may make statements according com- 

 pletely with facts and phenomena, and leading to the most 

 complete understanding of every-day truths. An empiric 

 may utter the most glaring absurdities, utterly out of 

 harmony with anything in heaven or earth, or under the 

 earth. Is Prof. Stokes therefore to be styled unpractical, 

 and Prof, (shall we^say) Pepper practical ? 



Push the matter to an extreme, and you can enunciate 

 sentences like these. If you want to know about steam- 

 engines and compound locomotives, you must go, not to 

 theorists like Rankine, or Unwin, or Cotterill, or even to 

 Mr. Webb. The driver of the Scotch express is the 

 man really able to give you trustworthy and practical 

 information. 



If you want to know the principles underlying the con- 

 struction of ships, and why some ships go quicker than 

 others, do not think of applying to the writings of the late 

 William Froude with his nonsensical paraffin toys, but 

 consult the captain of the Umbria or the City of Rome. 



We have set down these sentences as a reductio ad 

 absurdtim of some of the claims set forth in favour of 

 empiricism as against science, under the specious and 

 plausible heading of practice against theory : but really 

 they are not a whit more absurd than much that is 

 seriously argued ; and were they propounded under 

 favourable auspices to an average British audience, they 

 would very likely be swallowed without nausea. The ex- 

 periment is almost worth trying, only it would be difficult 

 for anyone himself faithless to avoid some suspicion of 

 irony, which would be fatal to success. 



Space may be afforded for a few more very brief extracts 

 from some of the engineering and technical journals 

 during the past month. The first is so choice as to need no 

 comment : — "The world owes next to nothing to the man of 



pure science The engineer, and the engineer alone, 



is the great civilizer. The man of science follows in his 

 train." This doctrine is explained and illustrated by 

 insistence on the futility of Faraday's work in connection 

 with magneto-electricity, until taken up and realized by 

 the practical man. 



In the same paper, a week later, occurs the following : — 

 " No one knows anything with certainty about lightning 

 outside of the common knowledge possessed by most 

 fairly educated people." And again, " We fail to see that 

 what is true in the laboratory must be true out of doors." 



This is interesting as an almost exact reproduction of 

 one of the historic objections made to Galileo's unwelcome 

 discovery of Jupiter's satellites. It was then similarly 

 maintained that, though the telescope was all very well 

 for terrestrial objects, it was quite misleading when applied 

 to the heavens. 



An instance of a converse proposition is told in a recent 

 popular work on astronomy (is it Sir R. Ball's ?), about a 

 farmer and amateur astronomer, who came to the writer 

 with a revolutionary system of astronomy, based upon a 

 number of observations which he had taken with a sex- 

 tant of the altitude of the heavenly bodies. The gentleman 

 had thus found that the generally received opinion about 

 the distances of the fixed stars was extremely erroneous. 

 But on inquiry it turned out that his altitudes were all 

 calculated on the common-sense and well-known fact that 

 sixty-nine miles make a degree. Finding it impossible to 

 get the gentleman to put his mind into an attitude for 

 receiving any instruction on the theoretical subject of the 

 measurement of angles, the representative of the orthodox 

 clique who impose their statements on the world as some- 

 thing more trustworthy than common information pre- 

 vailed on the gentleman to apply his sextant to determine 

 the altitude of his own barn. This reductio ad absurdum 

 was avoided, however, and the overthrow of orthodox 



