THE LUMINIFEROUS ETHER.

Timaru Herald, Volume LVII, Issue 6066, 27 September 1894, Page 4

THE LUMINIFEROUS ETHER.

— ■»...— Lord Salisbary m his presidental a3d rose to Ihe British Association, spoke as follows regarding tbe ether :— The next discussion to whioh I should. look m order to fird urejhod riddles which have hitherto defied tae scrutiny of scienoe, would be the question of what is called tbe etber. The ether occupies a highly anomalous position m the world of scienoe. It may be described as a half 'disoovere'l entity, I dare not use any less pedantic word than entity to designate it, for it would be a great exaggeration of onr knowledge if I were to speak of it as a body or even as a substance, When nearly a century ago Young and Fresntl discovered that the motions of an incandescent particle were conveyed to our eyes by undulation, ii followed that between our eyes and tbe particle there must be something to undulate. In order to furnish that something, the notion of tbe ether was con ceired and for more than two generations tbe main, if not the only, funotion of the w rd ether has been to f urniah a nominative case to the verb •to undulate ' Lately, our conception of this entity has received a notable extension One of the most brilliant of the services whioh Professor Maxwell has rendered to science has been the disoovery that the figure whioh expressed the velocity of light, alao expressed the multiplier required to change the measure of static or pasoive e'eo tricity into that of dynamio or aotive electricity. The interpretation reasonably affixed to this disoovdry is that, an light and the electr'c impulse mova ap.,' ximtitely at the same rate through spaoe, ii. v probable that the undulations which convey them are undulations of the same medium. And as induced electricity penetrates through everything, or nearly everything, it follows that the ether through wbioh its undulations are propagated must pervade all spaoe, whether empty or full, whether occupied by opaque matter or trans parent matter, or by no matter at all. The at* traotive experiments by whiob the late Professor Herz illustrated the eleotrio vibrations of ! the etber will only be alluded to by me,m order that I may express the regret deeply and generally felt that death should have terminated prematurely the scientific oareer whioh had begun with ouoh brilliant promise and euoh 'ruit'ul | achievement*. But the mystory of the ether, though it has been made more faioinatiog by ! these discoveries, remains even nure inscrutable than before. Of this all-per»sding entity we know absolutely nothing except this one fact, that it oan be made touodulaie Whether, outside the influence of matter on the motion of the wav 8, ether has udv rfff ct on matter or mater upon it, is absolutely unknown. And even its tolitary function of undulating, ether performs m an abnormal fashion which has caused infinite perplexity. All fluid* that we know transmit any blow th y have reoeived, by WBves whioh undulute btck wards and forwards m the path of their own adraDoe. tbe etber undulates athwart tbe path the wave* advance- Ihe genius of Lord Kelvin has recently ducovewd what ha terms a lsbH^'ftato of (q'ii'.ibrium, m which a fluid that is infinite ia its eilett may exist, and may undulUe m this eccentric fa»h'ou without outraging the laws of mathematics. lam ne mathematician, and I cannot ju go whether '. tbie reconciliation cl the eotiju of tbe ether with mecn&Dioal law is to be looked upon as a permanent solution of the questiou or is only what diplomatists call a roodu* vivmdi. In any cane it leaves our knowledge of the ether m a very rudimentary condition, It has no known qualities exueot ono, and that quality ia iv thn highest degree snotnajjut and in* scrutable. Tbe extended conception whiob enables ub to recognise ethereal waves m the vibrations of electricity has added infinite attraction to the stufy of thoae waves, but it car rice its own difficulties with it. It is not easy to fit m the theory of electrical ether waves with tbe phenomena of positive and negative electricity, and bb to tbe true significance and oause of those counteracting and complementary forces to whioh we give the provisional names of negative and positive, we know about as much now as Franklin knew a oetitury and a half ago.