November 19, 1891] 



NATURE 



63 



ELECTRICITY IN RELA TION TO SCIENCE. 



TH E third annual dinner of the Institution of Electrical 

 Engineers was held at the Criterion on Friday, 

 November 13. Prof. William Crookes, the President, 

 was in the chair. In proposing the toast of the evening, 

 " Electricity in relation to Science," Prof. Croo'<es deli- 

 vered the following speech : — 



We have happily outgrown the preposterous notion 

 that research in any department of science is mere waste 

 of time. It is now generally admitted that pure science, 

 irrespective of practical applications, benefits both the 

 investigator himself and greatly enriches the community. 

 " It blesseth him that gives, and him that takes." 

 Between the frog's leg quivering on Galvani's work-table 

 and the successful telegraph or telephone there exists a 

 direct filiation. Without the one we could not have the 

 other. 



We know little as yet concerning the mighty agency of 

 electricity. " Substantialists " tell us it is a kind of matter. 

 Others view it, not as matter, but as a form of energy. 

 Others, again, reject both these views. Prof. Lodge con- 

 siders it " a form, or rather a mode of manifestation, of 

 the ether." Prof. Nikola Tesla demurs to the view of 

 Prof. Lodge, but thinks that "nothing stands in the way 

 of our calling electricity ether associated with matter, or 

 bound ether." High authorities cannot even yet agree 

 whether we have one electricity or two opposite elec- 

 tricities. The only way to tackle the difficulty is to 

 persevere in experiment and observation. If we never 

 learn what electricity is, if, like life or like matter, it 

 should remain an unknown quantity, we shall assuredly 

 discover more about its attributes and its functions. 



The light which the study of electricity throws upon a 

 variety of chemical phenomena — witnessed alike in our 

 little laboratories and in the vast laboratories of the earth 

 and the sun— cannot be overlooked. The old electro- 

 chemical theory of Berzelius is superseded, and a new 

 and wider theory is opening out. The facts of electro- 

 lysis are by no means either completely detected or 

 co-ordina'.ed. They point to the great probability that 

 electricity is atomic, that an electrical atom is as definite 

 a quantity as a chemical atom. The electrical attraction 

 between two chemical atoms being a trillion times greater 

 than gravitational attraction is probably the force with 

 which chemistry is most deeply concerned. 



It has been computed that, in a single cubic foot of the 

 ether which fills all space, there are locked up 10,000 

 foot-tons of energy which have hitherto escaped notice. 

 To unlock this boundless store and subdue it to the 

 service of man is a task which awaits the electrician of 

 the future. The latest researches give well-founded hopes 

 that this vast storehouse of power is not hopelessly 

 inaccessible. Up to the present time we have been ac- 

 quainted with only a very narrow range of ethereal vibra- 

 tions, from extreme red on the one side to ultra-violet on 

 the other— say from 3 ten-millionths of a millimetre to 8 

 tenmillionths of a millimetre. Within this comparatively 

 limited range of ethereal vibrations, and the equally 

 narrow range of sound vibrations, we have been hitherto 

 limited to receive and communicate all the knowledge 

 which we share with other rational beings. Whether 

 vibrations of the ether, slower than those which affect us 

 as light, may not be constantly at work around us, we 

 have until lately never seriously inquired. But the re- 

 searches of Lodge in England, and Hertz in Germany, 

 give us an almost infinite range of ethereal vibrations or 

 electrical rays, from wave-lengths of thousands of miles 

 ilown to a few feet. Here is unfolded to us a new and 

 .istonishing universe— one which it is hard to conceive 

 should be powerless to transmit and impart intelligence. 



Experimentalists are reducing the wave lengths of the 

 electrical rays. With every diminution in size of the 



NO. I 151. VOL. 45] 



apparatus the wave-lengths get shorter, and could we 

 construct Leyden jars of molecular dimensions the rays 

 might fall within the narrow limits of visibility. We do 

 not yet know how the molecule could be got to act as a 

 Leyden jar ; yet it is not improbable that the discon- 

 tinuous phosphorescent light emitted from certain of the 

 rare earths, when excited by a high-tension current in a 

 high vacuum, is really an artificial production of these 

 electrical rays, sufficiently short to affect our organs of 

 sight. If such a light could be produced more easily 

 and more regularly, it would be far more economic tl 

 than light from a flame or from the arc, as very little of 

 the energy in play is expended in the form of heat rays. 

 Of such production of light. Nature supplies us with 

 examples in the glow-worm and the fire-flies. Their 

 light, though sufficiently energetic to be seen at a con- 

 siderable distance, is accompanied by no liberation of 

 heat capable of detection by our most delicate instru- 

 ments. 



By means of currents alternating with very high fre- 

 quency, Prof. Nikola Tesla has succeeded in passing by 

 induction through the glass of a lamp energy sufficient to 

 keep a filament in a state of incandescence without the 

 use of connecting wires. He has even lighted a room by 

 producing in it such a condition that an illuminating 

 appliance may be placed anywhere and lighted without 

 being electrically connected with anything. He has pro- 

 duced the required condition by creating in the room a 

 powerful electrostatic field alternating very rapidly. He 

 suspends two sheets of metal, each connected with one of 

 the terminals of the coil. If an exhausted tube is carried 

 anywhere between these sheets, or placed anywhere, it 

 remains always luminous. 



The extent to which this method of illumination may 

 be practically available experiments alone can decide. 

 In any case, our insight into the possibilities of static 

 electricity has been extended, and the ordinary electric 

 machine will cease to be regarded as a mere toy. 



Alternating currents have at the best a rather doubtful 

 reputation. But it follows from Tesla's researches that as 

 the rapidity of t^e alternation increases they become not 

 more dangerous but less so. It further appears that a true 

 flame can now be produced without chemical aid— a 

 flame which yields light and heat without the consumption 

 of material and without any chemical process. To this end 

 we require improved methods for producing excessively 

 frequent alternations and enormous potentials. Shall we 

 be able to obtain these by tapping the ether 1 If so, we 

 may view the prospective exhaustion of our coal-fields 

 with indifference ; we shall at once solve the smoke ques- 

 tion, and thus dissolve all possible coal-rings. 



Electricity seems destined to annex the whole field not 

 merely of optics, but probably also of thermotics. 



Rays of light will not pass through a wall, nor, as we 

 know only too well, through a dense fog. But electrical 

 rays of a foot or two wave-length of which we have spoken 

 will easily pierce such mediums, which for them will be 

 transparent. 



Another tempting field for research, scarcely yet at- 

 tacked by pioneers, awaits exploration I allude to the 

 mutual action of electricity and life. No sound man of 

 science endorses the assertion that "electricity is life" ; 

 nor can we even venture to speak of life as one of the 

 varieties or manifestations of energy. Nevertheless elec- 

 tricity has an important influence upon vital phenomena, 

 and is in turn set in action by the living being —animal 

 or vegetable. We have electric fishes — one of them the 

 prototype of the torpedo of modern warfare. There is 

 the e'ectric slug which used to be met with in gardens 

 and roads about Hornsey Rise ; there is also an electric 

 centipede. In the study of such facts and such relations 

 the scientific electrician has before him an almost infinite 

 field of inquiry. 



The slower vibrations to which 1 have referred reveal 



