296 



NATURE 



[December 13, 191; 



science, however recondite and however seemingly use- 

 less at the moment, find their practical application 

 sooner or later. It may not be for years or even for 

 centuries, but in its own time the application comes. 

 Invention is a faculty of the imagination, the inventive 

 temperament being akin to the iirtistic temperament, 

 and real inventors, like true artists, being born and not 

 made. In order to be great both must have creative 

 powers in a high degree. Unless gifted at birth with 

 the inventive afflatus, the ordinary man can no more 

 by taking thought make himself an inventor than he 

 can add a cubit to his stature. At the same time, the 

 inventor, to be fully successful, must be suitably 

 educated. By study and the acquisition of knowledge 

 he widens his scope, and can apply his gifts in fields 

 of invention to which, without such knowledge, he 

 could not hope to aspire. This notwithstanding, it is a 

 noticeable and curious fact that many great inventions 

 have been made by men whose ordinary vocations were 

 quite outside the particular field in which their inven- 

 tions applied. This is no doubt a case of the fresh 

 mind of the outsider looking at things from a_ new 

 aspect, whereas those who are daily working in any. 

 particular line are apt to get into a groove and to be 

 trammelled by usage and convention. Perseverance, 

 and a capacity for continuity in keeping to one subject, 

 are outstanding qualities to be observed in all success- 

 ful inventors. Many with brilliant ideas fail for lack 

 of these. As has been justly said, great discoveries 

 are never, and great inventions very seldom, the work 

 of a single individual. 



At certain periods the general state of progress, 

 both in pure and in applied science, renders particular 

 inventions possible, with the result that a number of 

 persons gifted with the necessary imagination almost 

 simultaneously attack the problem. In such cases, if 

 one individual inventor had not succeeded, it is prob- 

 able that another would have done so, though perhaps 

 in some slightly different manner. 



For these reasons in all these cases it is very difficult, 

 if not impossible, justly to apportion the credit. The 

 public and the Press usually award it all to the indi- 

 vidual who makes the first practical and commercial 

 success, being entirely ignorant of all the previous 

 stages that have led up to the final result, and oblivious 

 of the fact that, without the vast amount of previous 

 research by other workers, the final inventor would never 

 have had the data wherewith to achieve what he did. 



On the other hand, a contrary and equally mistaken 

 view is not seldom taken by the workers in pure 

 science, who, absorbed in the intricacies of their own 

 achievements, are prone to underrate w-hat the actual 

 inventor accomplishes, usually by slow degrees, and 

 with infinite pains and patience. They, further, do not 

 understand what a long step there is between the mere 

 idea and the worked-out invention, and how much 

 labour, practical ingenuity, and perseverance, and also 

 how much money an invention usually requires to 

 make it successful and to get it taken up industrially. 

 Indeed, this last-mentioned commercial operation is 

 frequently the most difficult of all to bring about, par- 

 ticularly as it is not common for inventors to be good 

 men of business. 



The history of particular inventions is frequently in- 

 structive, and a good instance is that of wireless tele- 

 graphy, which is comparatively recent, so that we 

 know all about it, and can follow accurately each single 

 step in its development. 



It, moreover, shows how pure and applied science 

 are indissolubly interwoven, and how the one is de- 

 pendent upon the other. 



According to modern views, enunciated in the first 

 instance about the year 1807 by Thomas Young, light 

 consists of undulations or wave motions in a hypo- 

 thetical ultra-material substance, known as the aether, 

 NO. 251 1, VOL. 100] 



: which is supposed to fill all space, permeating the solid 

 I earth, the planets, the stars, and all material objects, 

 ! and reaching to the utmost limits of the universe. Just 

 ' as sound is known to be a wave motion in the air, so 

 ! light is believed to be a wave motion iri this hypo- 

 I thetical aether. About the year 1870 James Clerk Max- 

 i well, professor of physics at the Cavendish Laboratory 

 j at Cambridge, chiefly by mathematical reasoning, 

 showed the close connection between electricity, mag- 

 I netism, and light by demonstrating that all three couJd 

 be explained on the basis of motions and stresses in 

 the eether. Thus, according to Maxwell, light was an 

 electro^magnetic phenomenon, and consisted of disturb- 

 I ances in the aether of exceedingly short wave-length, 

 I whereas longer waves and stresses in the same medium 

 i explained the phenomena of electricity and magnetism. 

 I As mentioned. Clerk Maxwell's discovery lay purely 

 in the land of theory, discovered mathematically, and 

 he attempted no experimental proof. Some twenty 

 years later Heinrich Hertz, by a series of most beau- 

 tiful experiments, proved the truth of Maxwell's theory. 

 By means of suitable apparatus he first of all created 

 electro-magnetic waves, and then with other apparatus 

 he detected them, showing that they could be reflected 

 and refracted, and, in fact, obeyed all the laws with 

 which light is known to comply. Indeed, so com- 

 pletely was this accomplished that, on hearing of it. 

 Lord Kelvin exclaimed that Hertz had annexed the 

 whole science of optics to the domain of electricity. 



Up to this stage nothing in these investigations had 

 hinted even in the slightest degree at any useful appli- 

 cation. Neither Young, nor Maxwell, nor Hertz was 

 moved by any other ambition than a curiosity tQ ex- 

 plore the nature of things. On the other hand, had it 

 not been for their labours, what was to follow could 

 not possibly have occurred. 



Hertz died young, almost immediately after making 

 the experiments to which allusion has been made, but 

 his work was taken up and largely extended in this 

 country by Sir Oliver Lodge. Hertz's experiments had 

 been on an exceedingly small scale, while Lodge em- 

 ployed, for creating his waves, methods which gave a 

 much greater power; moreover, as a detector ot these 

 waves, Lodge used an exceedingly delicate instrument, 

 which he christened the coherer. This was due to a 

 discovery by Branly, of Paris, who also was investi- 

 gating Nature without any ulterior utilitarian aims. 



Lodge, no doubt, was impelled by similar motives, 

 but having a practical mind he threw out the sugges- 

 tion that the Hertzian waves might possibly be em- 

 ployed for signalling. Indeed, he went so far, at a 

 lecture which he gave at the Royal Institution in 1S94, 

 as actually to ring a 'bell by this means from one end 

 of the building to the other, through the thickness 

 of several partition walls. In the same year, at the 

 British Association meeting at Oxford, he transmitted 

 similar signals over vet greater distances. 



These experiments of Lodge led several persons to 

 consider whether the method was not applicable to 

 telegraphy, but nothing practical was done until Mr. 

 Marconi, who was acquainted with the work of both 

 Hertz and of Lodge, and was impressed with the 

 possible commercial value of the idea, came upon the 

 scene, and with great skill very soon showed that it 

 was feasible by Hertzian waves to telegraph across 

 the Channel, and even over much longer distances. 



The rest of the history of wireless telegraphy, very 

 interesting though it is, does not concern us here, for 

 what I wish to impress upon you is how, in this 

 instance, as in many others, researches and experi- 

 ments in pure science, which, so far as their authors 

 could see, showed not the faintest sign of any practical 

 application, led in time to inventions of the greatest 

 possible public utility. Many years elapsed between the 

 researches and theories of Young and Maxw-ell, the 



