SCIENCE NOTES.

Otago Witness, Issue 2823, 22 April 1908, Page 76

SCIENCE NOTES.

-An improved "pedestrian catcher," to pfcveii- accident to persons run down by traiccars, is attracting attention m Dresden. It is easily attached 1 co cars, does not get out of order, and"- picks up and' carries along life-size leathern maunikin3 ; living dogs, and even bottles filled with, liquid. — A. .new canal co connect the River Rhone with the port o; Ma.—eilles will pass through a tunnel four and a-quarter miles long The tunnel will be 72ft bread, and 46ft high. The quantity of material to be removed- m. constructing this tunnel :s dou&ie that removed m the construction of the Simplon. The differences- arise from the great width and height of the canal tunnel. The titne required for digging it is seven; or eight years. — Tire health- qualities of lemonade aave long 'been popularly celebrated, and recent scientific research shows that this pleasing sunur-er drink deserves its reputation. M-. Riegel, writing m the Archives- of Hygiene, says that m a- lemonade containing six grams per litre, of citric acid" tke bacillus of ehc.-lera. is- killed:- m half an- hour, and that of typhoid m 24-' hours. But when the same lemonade is permeated xith sunshine,, the? cholera- Bacillus ; perishes- in five minutes and 1 * the typhoid bacillus m two hours. —It i 3 announced that a French inv'o.n•ior has discovered' a cheap and easy pro-., oesa.' by means- of whidh thread similar m texture- to csfcton or lineny. and possessing greit strength, can be maiui factured from paper. -So.deiaHs of the- method of" pro deletion- are vouohsafed', but ihe'- thread is. stated to> ba- suitable for * -«f."iefcy of purpeees, .-inch a*, dress 1 materials for ladies'' Mstirmes, being impervious to damp, amd aot inflammable It o&iv also be ieed' for the manufacture of bags, towels, hats-. and: so forth: If. :s claimedi that the thread? can- ber made at » cost cf- 90 per cent, below that- of linen, and' some 80 per cent less' than that of cotton. ! — Professor Schafer believes thafc daylight alone determines: bivd : migration. Thesumzn«r migrantsi he tells ue: go' north to take advantage- of the longer dajs, it-nd go south attain- to &void tire short and' dark ones. They require all their time to ?et sufficient food- for themselves' and their voracious young, and hence the extra daylight of the north- ie summer is an advantage to them, iin winter the short days do not allow t-hevn to get sufficient. Most birds require daylight for feeding. Professor Schafer dees not credit the old explanation that migration is due to cold and want of food. Many species leave Eurone while the weather is •warm and focd .till abundant. — There are not many people nowadays 'says Science Siftines) who can walk any distance »fc all without feeling nsed ut). Walking is becoming less necessary each year, fcr public vehicles are confcinuajiy increasing m number. The children of this Iteration, do; nob waik • a* much as did. the children of ths last generation. Each. futurrr generation- will walTt less than th/> one that preceded it,' 1 until' the time will probably come when 1 people will jra-tl- it impossible 1 to wvlk. except m n- tarv limited way. And' tfrfio knows, but A^eX. fc'nre in<w finally cepie- . Th*n people- caai-'fc walk at all:!' Stranger things than that have happened. It is an. inevitable law of sT*t-«** that the pari <a? the ihsdy- which, is-, not used m time becomes, useless* — iSie- nrob'-errr. of right--hard-sdne«s. Dr G-aorgfe _3f. Gould concludes, is solved by two military, and so«ial- facts : — Jlj- From- the first Jse of imfplftme_it« of offence and defe.ice. the left or heart side h?.s heen protected by the shield, and the left hand has been -called the shield"- hand:; (2) and. the fi;ee o_ rig&t hand wa3 not only employed for the spear, but for counting m primitive barter, and othe:* purposes, becoming necessarily dominant m all active: operations. The oeculiariiy seems to be entirely absent m.. ib-.^«?- animals. Bfe[uisre?s that hold -:uts m their fore pa.ws, - cats, that strike insects or plsv with mice, and' even monkeys siid gorillas, give no susjppstion of a prefcrencn fair paw or eye of either right or I'sft side. — Arccrdhsnp to r'weni reports-. J_ake-Tahoe. m the Sierras*, iss _ai_r_.pt c-api>sUy. Tfee lake j« situated on the boundary ofi Meyada and California., riser Reno,. Nev. About a month ago it was observed that the waterstvere receding. In four weeks' time they had dropper, fully 6ft. Tbe cause of the subsidence is a mystery. Two years a,?o the waters rose rapidly to such, a height that the surrounding towns were seriously theatened*. The lake is very deep, and is situated m what, some believe to be an extlnat volcano. Possibly tlie mysterious /changea of level may be due to. voioanic action. Accdrdirnor to. a legend, of the Waishoe Indians^, the waters once were Jitirie^ out of the lake by some subterranean force, and overwhelmed the inhabitants of :own» m. the va,i!ey to t te east. — 3Sor many experiments now it is necesiwtry to exclude all outside sound. What fa endorsed by Professor £. I. Franz ac the one a. »*o!ate_jr ~oise!.ees room is a roota abo-.it Bft sruare'Nii'd high on the top fl oor of the pliv.-.iologics.! iabo™arory of th« University of TTtrecKt. Its wails are scout llin thick. From the iiicide kh*we ft-e iw^e v,p of siiccesaiye '.uvers of horsehair, felt, porous stone, dead air, wood partition, grouift- co-'c com.pr'iuion:. and' a plaeteredsurface. Ti-.e ceiling: though somewhat sHnpler Jia<Je, has similar la-y«rs. The board* of the ffie»>_ were» sa^rW- anJ 1 the joints filled with lead to stop vibration, a layer of lead was then cohered' aver ail to the ihiokness of more than an rnob^ and. ove:- _ this m turn is used a carpet neaa*!^ . Uin m thickness, n.nd sometimes' a se^rr-d carpet. A small window opens into a !jtfle> connected room witli* a roof window, thetwo windows suwdyin^- bnth> sunlight an<J yentila-tTom The door Is detrbV, the outer pirt accurately fitted with felt, and the inaioi- part eompeeed of three layers with mi air space. — 'She F_cams G*n*_ Cornmis«ion has: deojdod upon- an fnrportant revision, of the -plans- for- t£e iocks near the PJwsific fcer- . jMim_s e*f the: Panama eanaiv -which _wiiT: result m. conajderablff eeenomy,. aaidi will place 'the lock* m at much betier defensive- pssition. The earliea- plana provided for the construction o£ two largre- <_ams, one the La Ifcoo-San Juan, a> male fn length, the other the SosA-Corozal dam, a mile and d -quarter lonjap. These eferuairurea wonld liflveformed a lak*, two miles- wide and four miles Jit •Eengtfii. and would haso necessitated the relocation o£ the- Panama railroad »nd the buikiing df « spillway from Soza __ake to the sea. The- near vStoat. nail* fo» ihe oonsfcEuetion. o£ * single dsaia- at. Mrraflores, tmiv half sl nriie Tong. m wbich will be built the two locfe. by wbiefc pnips will be raised from sea level to tn<* 55ft level. A ohannel 500 ft wide- wilt lea^ from fche

locks to the Bay of Panama, and this chaiu nei wiU lie m material that can be excavated entirely by dredges. Another advantage of the ciiange is that the Mirafloras dam will be founded everywhere upon rock, which the numerous 6ft by Bft test pits have shown to be present throughout the whole site. The change will aiso tear] to some economy of time m transit, since ships vrill be able to steam at good speed through the 500_t channel direct from the- sea to the ioc-ks. The importance of the change can scarcely be over-estimated. The security of the danal is greatly increased by the removal of the dim and locks some four miles farther out of the range of an enemy's guns; the target is much smaller; and it is estimated that because of the reduction m size of the work- and the greatly reduced depth to rock foundations, there will be a total saving of about eight million dollars over the former plans.— Scientific American. — Scientific investigation has just disj'oo&ed the amazing fact that the lobster is the swiftest, of all the sea's inhabitants. Ho travels at the rate of 25ft m less than a seoond. Marine architects and engineers are studying tho lobster with a view of modelling future ocean ieviathans on his lines. They hope thereby to build a boat which will cross the Atlantic mi three days. 'If an ocean steamship could travel m pro- . portion to its length and size as fast as a_ lobster, it *ould cress m a few hours. ' l4e_;ce the question is seriously asked, is the. lobster to- jjiva a new and amazing i.ro>e.*u.a io h, u eam navigation? Is the lobster 'a:, -natta, ..rate an epoch m navigation m. which all existing speec-aniashing records .shali be "c.-gocfen? It haa taJcen many i years fo.' the Atlantic liners to make the , five-day trip. Now there aire marine i architects who are seriously aoniemplatihg. ; the building, of a boat that will give: ua a. ' ihree-day trip, without pausing to pass 'jiiEougE- the four-day stage. And iheir hopes of attaining this marvePous result 'are built upon the lobster, the plain, every- ! day, or every-nighfc lobster ratherT* for this 'crustacean is nocturnal, m hia habits. Dr Francis Hobart-Herrick has discovered that the lobster can shoot through 25ft of space m less than a second. The first boat floated | was- modelled on a fish. Ts it surprising 'that man should again go to a resident of i the deep for lessons m the arts of* ship.'building and navigation? — but this time- to a s^a dweller of another order, to the King '«f the 1 Crustacea, a title bestowed upon him- , by reason of his size and his strength, his j abundance, and- his economic value.