Nov. 15, 1883] 



NA TURE 



57 



cal miles an hour, or 2'6 miles per minute; less than half the 

 rate at which the great shocks of 1755 and 1761 crossed the 

 Atlantic from Lisbon to Barbados, which is given by Mallet as 

 7 '3 miles, or 6 '3 geographical miles per minute.' 



J. H. Lefroy 



" Partials " 



In your number of Nov. i, p. 6, I noticed an article the object 

 of which was t ; account for the e.Kistence of "partials." Were the 

 theory therein set forth correct, we should have a constant number 

 of "partials" for any given "fundamental" tone of constant 

 force regardless of its source ; whereas it is a well-kncwn fact 

 that, while the tones of some instruments are rich in " partials," 

 those of other instruments have but few. 



Cromwell O. Varley 



Cromwell House, Bexley Heath, Kent 



SCIENCE AND ENGINEERING 

 T N the address delivered by Mr. Westmacott, Presi- 

 ■*■ dent of the Institution of Mechanical Engineers, to 

 the English and Belgian engineers assembled at Liege 

 last August, there occurred the following passage : — 

 " Engineering brings all other sciences into play : chemi- 

 cal or physical discoveries, such as those of Faraday, 

 would be of little practical use if engineers were not 

 ready with mechanical appliances to carry them out, and 

 make them commercially successful in the way best suited 

 to each." 



We have no objection to make to these words, spoken 

 at such a time and before such an assembly. It would 

 of course be easy to take the converse view, and observe 

 that engineering would have made little progress in 

 modern times, but for the splendid resources which the 

 discoveries of pure science have placed at her disposal, 

 and which she has only had to adopt and utilise for her 

 own purposes. But there is no need to quarrel over 

 two opposite modes of stating the same fact. There is 

 need on the other hand that the fact itself should be 

 fairly recognised and accepted, namely, that science may 

 be looked upon as at once the handmaid and the g^ide of 

 art, art as at once the pupil and the supporter of science. 

 In the present article we propose to give a few illustrations 

 which will bring out and emphasise this truth. 



We could scarcely find a better instance than is fur- 

 nished to our hand in the sentence we have chosen for a 

 text. No man ever worked with a more single-hearted 

 devotion to pure science— with a more absolute disregard 

 of money or fame, as compared with knowledge — than 

 Michael Faraday. Vet future ages will perhaps judge 

 that no stronger iinpulse was ever given to the progress 

 of industrial art, or to the advancement of the material 

 interests of mankind, than the impulse which sprang from 

 his discoveries in electricity and magnetism. Of these 

 discoveries we are only now beginning to reap the benefit. 

 But we have merely to consider the position which the 

 dynamo-electric niachine already occupies in the industrial 

 world, and the far higher position which, as almost all 

 admit, it is destined to occupy in the future, in order to 

 see how much we owe to Faraday's establishment of the 

 connection between magnetism and electricity. That is 

 one side of the question — the debt which art owes to 

 science. But let us look at the other side also. Does 

 science owe nothing to art ? Will any one say that we 

 should know as much as we do concerning the theory of 

 the dynamo-electric motor, and the laws of electro-mag- 

 netic action generally, if that motor had never risen (or 

 fallen, as you choose to put it) to be something besides 

 the instrument of a laboratory, or the toy of a lecture- 

 room. Only a short time since the illustrious French 

 physicist, M. Tresca, was enumerating the various sources 

 of loss in the transmis-ion of power by electricity along a 

 fi.xed wire, as elucidated in the careful and elaborate ex- 



• Mallet's Fourth Report, British Association, 1S58. 



periments inaugurated by M. Marcel Deprez, and subse- 

 quently contmued by himself. These losses — the electrical 

 no less than the mechanical losses — are being thoroughly 

 and minutely examined in the hope of reducing them to 

 the lowest limit ; and this examination cannot fail to 

 throw much light on the exact distribution of the energy 

 imparted to a dynamo machine, and the laws by which 

 this distribution is governed. But would this examination 

 ever have t.iken place — would the costly experiments 

 which render it feasible ever have been performed— if the 

 dynamo machine was still under the undisputed control 

 of pure science, and had not become subject to the sway 

 of the capitalist and the engineer ? 



Of course the electric telegraph affords an earlier and 

 perhaps as good an illustration of the same fact. The 

 discovery that electricity would pass along a wire and 

 actuate a needle at the other end was at first a purely 

 scientific one; and it was only gradually that its import- 

 ance, from an industrial point of view, came to be recog- 

 nised. Here again art owes to pure science the creation 

 of a complete and important branch of engineering, whose 

 works are spread like a net over the whole face of the 

 globe. On the other hand, our knowledge of electricity, 

 and specially of the electro-chemical processes which go 

 on in the working of batteries, has been enormously im- 

 proved in consequence of the use of such batteries for the 

 purposes of telegraphy. 



Let us turn to another example in a different branch of 

 science. Whichever of our modern discoveries we may 

 consider to be the most startling and important, there 

 can I think be no doubt that the most beautiful is that of 

 the spectroscope. It has enabled us to do that which but 

 a few years before its introduction was taken for the very 

 type of the impossible, viz. to study the chemical compo- 

 sition of the stars ; and it is giving us clearer and clearer 

 insight every day into the condition of the great luminary 

 which forms the centre of our system. Still, however 

 beautiful and interesting such results may be, it might 

 well be thought that they could never have any practical 

 application, and that the spectroscope at least would 

 remain an instrument of science, but of science alone. 

 This however is not the case. Some thirty years since 

 Mr. Bessemer conceived the idea that the injurious con- 

 stituents of raw iron — such as silicon, sulphur, iS:c. — might 

 be got rid of by simple oxidation. The mass of crude 

 metal was heated to a very high temperature ; atmospheric 

 air was forced through it at a considerable pressure ; and 

 the oxygen uniting with these metalloids carried them off 

 in the form of aad gases. The very act of union gene- 

 rated a vast quantity of heat, which itself assisted the 

 continuance of the process ; and the gas therefore passed 

 off in a highly luminous condition. But the important 

 point was to know where to stop ; to seize the exact 

 moment when all or practically all hurtful ingredients had 

 been removed, and before the oxygen had turned from 

 them to attack the iron itself. How was this point to be 

 ascertained.'' It was soon suggesttd that each of these 

 gases in its incandescent state wojld show its own peculiar 

 spectrum ; and that, if the flame rushing out of the throat 

 of the converter were viewed through a spectroscope, the 

 moment when any substance such as sulphur had dis- 

 appeared would be known by the disappearance of the 

 corresponding lines in the spectrum. The anticipation, 

 it is needless to say, was verified ; and the spectroscope, 

 though now superseded, had for a time its place among 

 the regular appliances necessary for the carrying on of 

 the Bessemer process. 



This process itself, with all the momentous conse- 

 quences, mechanical, commercial, and economical, which 

 It has entailed, might be brought forward as a witness 

 on our side ; for it was almost completely worked out in 

 the laboratory before being submitted to actual prac- 

 tice. In this respect it stancls in marked contrast to the 

 earlier processes for the making of iron and steel, which 



