SCIENCE NOTES.

Dominion, Volume 1, Issue 179, 24 April 1908, Page 3

SCIENCE NOTES.

PHOTOGRAPHING THE INVISIBLE.'

AMAZING EXPERIMENTS WITH - ' ELECTRICITY. ' Is it possible to take photographs of tho invisible? The answer. of the average man would be in the negative, but Mr. Frederick Hoyenden says it is. possible, and is prepared (says the London "Daily Express") to prove by experiments that not only can the invisible: bo photographed, but that, the results can be reproduced by' means of the -cinematograph: Mr. Hovenden, besides being a vice-president of the London Institution, is a Fellow of the. Physical Society of London,- a' Follow of the Geographical Society, a Fellow of the Linnean Society, and a Follow of the Royal Microscopical Society. He has agreed to give four lectures on "A Studv of the principles of Nature" at the' London . Institution, and in the course of these lectures'he h?pe3 to.prove to ,tho satisfaction of a critical audience-tho truth, of the following statements :— ' . ' (1) That electricity, '■ heat, and other are tho same thing, and consist' of a ■ fluid which if properly illuminated, will ,' bo visible to the naked eye. (2) That,'it is possible to take cine- , matograph pictures of tho' invisible. /. (3) That the. ordinary human being ex- ■ hales electricity or ether through the • : pores of the skin at tho tips/of the finger. -• '.v •: , • • ' (4) That, photographs. of this electricity, which, nnless , specially illuminated is; invisible, • can be taken and reproduced by tho cinematograph. . Mr. Hoyenden gavo a private view of the principal experiments by which he claims to prove his theories to an "Express" representative, and illustrated tho manner in which tho. photographs.-of air moving, in-'air —which are to be 'reproduced at his lecture by means, of- tho cinematograph by Mr. F. Martin taken. ■'•' :[ ' Ho first fills a' square glass box, which is, technically, known as an "analyser," full of ordinary tobacco smoke from a cigarette, and this is carefully mixed with the ordinary air. . Ho then places his finger through a hole in the bottom of the "analyser," and when the light from a powerful electric arc lamp is turned on, it is quite possible to see the ether—or electricity—issuing from the finger. ■,'..., Mr A Hovenderi explained that this electricity comos through minute holes in the top of-those ridges of the skin by which police system of identification 'by .fingerprint impressions is carried , out. Those minute holes are at times . visible to 'the naked eye when tho finger is carefully examined. The electricity can be seen'escaping {from the-finger even when'-tho .latter is„ covprc'd' by a tight-fitting indiarubbercap. ■' ./ .j- ■ ;; .v, ■ ■■■'' Another experiment proved 'that, .compared; with ordinary cigarette smoke, the air we breathe is jet black. The co'rk' froin tho holo in the "analyser" 'was removed, and. the powerful light..was .turned pn the' box,"a- coal-black'-stream' of: air. could, be seen entering through the opening. . Cinematograph v ; ofthis air have also' been taken, and" jwhen thrown on tho screen tho minute molecules., of which tho air is made up can bo magnified to the jizo -of-balls five, or six feet in diameter. \ " Although many scientific exports maintain .that it is 'impossiblo; to ; sco molecules -of' smoke undor .a\.microscopo, Mr.\ HoyPridcn, showed them by. means l of a; special mstru-' ment'.to tho- "Express" . representative; When greatly magnified they .have tho ap-. pearanco of small snakes of a semi-circular, shape 'which .float gracefully through tho air, swaying gently- first to one- side and then to'the other. .... . Mr. Hovenden then illustrated 1 the manner, in Which he .will; .pro'vo that, tlio/fluid "which. issues through the. 'pores at tho tip of tho-finger is electricity.. Ho placetl his finger beneath tho, metal end of a galvanometer—an instrument which at. once records any chango in the chrrent of electricity passing through itr—and immediately tho recording disc showed a. considerable increase ' in the 'voltage. This increase was equally noticaablo when tho finger had the j india : rubber, cap on it. ; ■ Another interesting experiment'. enables Mr. Hovenden - to give the appearance of flame to any evaporating>liqiiid. This is done by turning the concentrated' ra.vs / from tho powerful'-'electric; arc; lamp ■ qn 1 th<? . vapour as it rises: .It, may-'bp mcntioricd' that this can' be seen in' any factory town whorethe illuminations reflected from, the roaring furnaces give tho appearance of .flame tortile, vapourland smoke issuing"from' the -tops\ of the chimneys.; , . , • » •; ' . ■ BRAIN'S: WHITE MAN v..NEGRO. • , "A white man's brain grows larger than the brain of < an African,": says Dr.' Simon. Krobbs. "This is a raoial characteristic,' that : scientists ..hayc .been aware of. foi years. A negro's skull solidities,; the sutures 'grow.together and there is no.room for,.further brain .development'.'' T.ho ■ --.little' ; negro child is as bright as tlie whito' youngster, bjit .when the <black ono reaches' ljis maximum tho' other's grdwth does not end l , so that by tho. time, they both, get .to bo twentj'-ono years of. age there is a great dis- : parity of'intellect. This is. tho reason why the negro ,has been for untold centuries, the world's labourer. , His jnentality .-.failing :to Jieep pacb with his physical 'development, he 'has become 1 a hewer' of w ; ood 'arid drawer' of water for his white-skinned brethren. Still another proof .of tho negro's thick head may vbe found by watching the. colou'rcd prizo fighters.' Have you-over noticed tho grand muscular showing they make in,the ring; their; superb endowment ,of torso (the trunk of the body) ? Their physical poirits are on a par with the best, but you ;will [notico that they all. have''tho' bullet-sliaped skulls, set' on grand'shoulders. . These '.'thick skulls, by the'way, afford thefn imiriense protection, as blows on the head that would nearly kill a. white fighter hayo no effect oiutho Sonegambian. \ In their stomachs, hoirever, they aro quito as vulnerable, and that is whero tho negro pugilist can't stand punishment. If blows , are constantly rained on this part of his anatomy, he is more apt to givo up the contest." . . SATURN'S RINGS. Saturn's rings aro turned nearly edgewise .to tho earth, for tho first timo sinco 1891,' . and several astronomers havo been studying certain knots that are to be seen' on' what formerly appeared smooth rings. Professor / Lowell has suggested that, this indicates disintegration, portions of the rings having fallen to tho surface of the planet. Dr. S. A. Mitchell offers the .reassuring prediction that Saturn's rings will appear as beautiful to , our grandchildren as to us now,., and points out that Clerk Maxwell demonstrated sixty years ago' that the rings must consist of millions of tiriy satellites rotating independently—finding it easy 'to show ithat there may be crowding in some places. THE SUN. Sir David Gill in a recent lecture, commenting on the fact that the sun seems to bo a huge , body of compressed gas, observed that-whether that gas was in a solid stata he was not prepared to: sa y ; ,) 10 thought not. Ho thought that when that gas began to solidify we should bo at least in tho period of beginning to get cool. But at present ho believed—lie did not know, and nobody know —that that gas was probably in a kind of viscous (sticky) condition, which was hot fish, flesh, or good red. herring. Outside tho,sun, apparently, they had a tremendous atmosphere, arid there wore enormous vortices, a development of energy and a throwing up of volcanoes, against which- our twopenny-halfpenny /volcanoes were nothing at all. Having tho sea in our own blood, and owing her everything—for being our enemy she is our stimulus, and being'our ally she is our support—we Dutchmen feci a deep sympathy for tho Kaiser's love of the sea. No ono understands better what tho ocean means to industrious, commercial,' and , denscly,populated nations. — "Algemeen Handels-Klad,!i-Amsterdam. ■