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Show -I llleeBBBleB SCtfENmTOPICS. CURRENT NOTES OP DISCOV-ERY DISCOV-ERY AND INVENTION. tli. Blfirtt Canter CTtr Until Takee run nit hf rit. ri A Hid for Dh la tli Ita.y Wrloo. la-eBtUne. To Ilava Te.th Ilk fearl. The reckless manner In which most leoplo abuie their teeth l enough to naka their wortt enemy remonstrate eltb them The rare of the teeth thould tie begun In babyhood a oft toothbrush being uted twice a day by whoovcr hs tare of the Infant Ai toon na the flrtt teeth looeen the child houli lie tAken to n dentist to remove them, so the new teeth will have room After thla periodical vlelts should be made to the ilentltt A child ihould never be allowed to bite bread or crack nula with hi teeth for It la likely to chip the enamel. The teeth to be kept In proper order and to look white and Immaculate, thould not pnly be bruih-ed bruih-ed night and morning, but after every mml In the day, Thajoothbruah muitj btlSjrtira8n':yWmuTtrprojldeJ bras and tho glass it acta a a nonconductor non-conductor and eonsequtntly there la ury mush lew heat conducted than there would be If tbt bran and glass vera not Intercepted Tlio lUrtU a UomMlelt. A writer In Knowledge makes n vivid viv-id picture of the great belt of cloudi, tome 300 miles In breadth, which tur-rounda tur-rounda the earth a Utile north of tlio equator. Within this belt rains almost incessantly falta, sometimes In sheets, and the wind seldom stirs Ileforo tho Invention of itcamihlpi vessels becalmed be-calmed In the "cloud-belt" sometimes drifted helpless for weeks llvon now the crossing of this belt, whero everything every-thing la surcharged with moliture, Is a disagreeable tiperlenco for voyagers going from the north to the south Atlantic At-lantic ocean, or tlce versa The belt can be traced ncrcas equatorial Africa and aeroes the h u Ixthmus, and the great rivers Amaaon Orinoco, Niger Ni-ger Nile and Congo arise In these rain-soaked rain-soaked regions, which are like exhaust-lees exhaust-lees retervotra. The cause ot the equatorial equa-torial cloud-belt It connected with the trade-winds nnd In the course ot a ynr It oscillates north nnd south over a distance equal to about three times its own breadth. IXstixt Camera I trr Until. At the photographic exhibition at the Cryttsl palace London, there was rhown what la undoubtedly the largest camera ever made The camera was over ill feet high, It takes a plate six feet by five fret but this alio ran only be utlllied for lino work nnd ordinary copying as the 1-ctr screen necesiary for the hslf-tone process, can only be obtained up to about forty by thirty Inches It Is Intended that tho back part should be built Into tho partition wall of tho dark room to thst the latter lat-ter would really form the dark slide, otherwlio a holder ot suRldent dimensions dimen-sions would be extremely heavy and cumbersome l)y Inclosing tho rear ot the camera ns a dark room, the plate would he placed directly Into the back pyLifiUlnStf!naiti'.slpg:.hcJ in po-1 anv sire fmm whnU-ntaln UD tothVI 'iWKejraDoutslrmonths to benl. Tnr plcturo i howa how steel may be Ignited In tho liquid oxygon. It Is only necessary nec-essary to stick the point ot a steel pin Into a match, light It. and thrust the whole Into tho liquid air, to furnlab sufficient heat to communicate the Ore to the steel The Hon a llajra. It Is estimated, aaya Science Sittings, that the earth receives not more than one thousand-millionth part of the total to-tal radiation ot the sun's rays It any comlderablo proportion of this heat were concentrated upon the earth It would not only become uninhabitable, but become speedily consumed If the great accumulation ot Ice at the north pole wero placed at a point on which this tremendous heat could be focused It would melt at the rate of 300000,000 cubic miles ot solid Ice per second, and the beat Is estimated as mechanical energy, en-ergy, ut the rate of about 10000 horsepower horse-power to every square foot of lurfice. |