SCIENCE SIFTINGS.

Auckland Star, Volume XLV, Issue 128, 30 May 1914, Page 15

SCIENCE SIFTINGS.

THK DEKPEtsT I.AKKS. Ki-eent soundings in Like Tanganyika by Captain .laci.lis. of the (icrman Navy, showed a maximum depth of 4-lOOft.. and still greater depths arc reported to have I.H-en found by a lteltrian official. Accordingly this great African lake is. with the exception of 1,,-ike Baikal, the dei-pest body of fresh waiter in the world, iiiid further investigations may j prove it t" be even deeper than Baikal.! In the deepest places thus far found, its boit.mi I. iit least I,oooft. below sea-j level. I AUDIT NICOTINK. j Mr Stanley Hedgrove. in "Knowledge,'' j eliri.-llsscs illdetail the- chemistry "f IO"| liaciHj and nicotine, lie treats the latter i i.-. a poison, stating that its action in | a pun- state- is a t least as rapid as that | .if jirussic acid; but. on the other hand, j liiiuhes upon tiie great bo.neuts which! «mail ele:,s,.s .et nicotine may have upon tin- nervous system. Incidentally he mentions tlic tact that in the first murder .-.mmitt.-d with the help of a pure ii'kai e'ul iiicutine was ii'ed. No certain nnl idnte lei nicotine potion is known, but curare lessen... the mtißcular contraction ciiiisi-d by the drug, and in one case the effect "I a fatal dose of ni-.-o-tiiie- administe-ed te> a rabbit was com pli-tely counteracted by two injections "f the juice of romsnon watercress. VOX l-y. THIEF CATCHER. A novel burglar alarm lias heen i place,l im the markpt in (lermany. composed .ci a small metal disc, circular in I shape, v. hieji may easily be carried in i the v.-st peicke-t. It is so arranged that .i detonating ,;i;i may he ine.eri.ed and. so loaded, il becomes a terror to sneak thieves. Suppose a traveller is staying in a sira.njc hotel and findo that hp 'cannot 10-k his devor. He places a chair agaiiiist the door, and slips the disc under one of its legs. Should anyone- attempt tn enter the room the chair ie forced out of position, the discflips open and the cap exploder., awakening the sleeper. The disc, may be used under baggage, iv purses, under bicycle or automobile tyres, and in many oilier ways. I N VISIB LE MOTION. Motion im ii only clx. appreehended by the human brain whim it takes place within certain limits) of speed. The whizzing bullet, and the unfolding bud ■if the plan', alike seem to Lt Is> be stationary, beca-itfe their motions arc out:snle those limits. It is »pos&ibh.'. however, by the aid of cinematograph, to bring these mentions within the ken of the human consciousness, t-6 that now we ran watch a plant sprout, gro>w, bud, bloesom, and wither in a few minutes, ' o-r a -bullet, travel leisurely towards a fragile otrje.-t. break it skrwly and deliberately, and ithe.n flwat 'lazily to the gronnd -among the Jragnvcnts. In an article contributed to an American technical journal. '"Machinery." an ex.pla.in*.ion is given of how tite=c apparent, wonders arc achieved. If irks desiTrd to exhibit the operation of a. slowly moving piece ~f nKf-iianism. d-or instance. the <e-;ic:.ilin,_t crank . f the cunvrti- is I irrnpd very slowly s-o .is t,i take as few ! pictures ens possible, and yet. show continuous movement. In tnc case oi v plan-:, the rite is about one photograph , cry eight hours instead of an average rate of sixteen p.cry second. To the scientist. ajul teacher the prolonged or s'pewled-.p film offers invaluable aid. Suppose that it is desired to explain the reason why a lioHwv rubber ball can ba.l_jn-e itself so perfectly at the tap of a jet of iwaler. Ry -the means of high-speed pictures thp trail is shown to acquire a moUv.ii at the top of t'lw column of water, which tends te, keep it from goiueg off at ithe side. A high-.frequen-cy spark apparatus -which has been .pprfp<?tcd' hy a well -ten own <-.inema.liogiTa.phi'* .tirm ena-bles ,pi.-turefi to be t-akpn at the astoimdj ng rate of 1.200 per geecond, so t,ha.t -the path of thi' swiftest bullet can be Tegristeved and lraced wiih ease before the human eye.