SCIENCE NOTES.

Otago Witness, Issue 2805, 18 December 1907, Page 76

SCIENCE NOTES.

i — It' a human, necve fibre, TOej»str^ched| round the 'garth* ' containing -two - fyainsl Very fclose''?dgether, ft would, be 123, hauras bef6Ve/a' J fiead|£cKe" Jfl',',one ,£¥9"s hj^.felt in* the' other.' ■'Atf"e"fcfctfi& impulse circles* lief <^rtk < aa;«iWita^ i &b^[*b^ ; 'tinVswSn^-i ! 'TosreeomtoJa^gtfntSS with. that, objaet: are noW in, progress. "jA Jiuae-^electrio^fcign h*s : been* jgL^deof ot thfi pe<?qn&. pk-ttyrxtt-dn the- side? lookiiig towardSpPaxi^-iSij night., this illumi* nate* sin; shoes' lni£&Jsfe"l n i£&Jsfe" fn gu&nticf figtrres"-Which*'«nange every" If,; fOHad^practioalr^hese' fjfruree will be* njaced* on tjie .tap- at ■ tiaf tower, so' as Vy. \ be* seen: from, ail feeder foi^fmany ihiles. " '" ;. — &o;n;any. biwfa'*rftdeßtroyed !I y€ar-ly''for': cooking,, and, ihat-tEiininjftg purposes that in some countries they^hav^ioen-alßaOst exier- ; minated. 'The 6kle,/ m, Lpndoa of 'Biotic^ plumages , and" biird ~ wins, has been%kndwi\ -, •to reach "'morif^aiaiV "20,090,000 Jn- a year. ' .The destruction of 'tfie; bir^la was io great' in Ameri«n;hafr Hk^Bures been taken to,, stop it ,In swngequenee the'tfad^ -heiej has>h»d teittil. btek^oirsea^iills, partridges, . golden oriole, Ota?, -*• <- •_>-,^ - -' —Jf would, appear pfrom- recent statistics that we JPritfeh are. dying: out in -the cities. '■ In the year 1800 the number of children .was 33 per cent, of the population. In the year 1900 there were only 23 ocr cent. Fewer children, were born in the town's and more die t&ere. Physicians say this is due. to the many demands on' the time of the mothers, -.which makes thetrt neglect their, a>ild*en.^ i , <-].'. A » —A. new,, species of- coffee, named 0. humilis, from Sassandra, on the Ivory Coast, is described 1 by A. Chevalier in Comptes Rendus. TfieiJlaat' rarely, exceeds half a yard in 'height, and rarely bears more than three or foW" fruits, -'lite plant differs from all other wild species in having two seeds present in the fruitr - The plant is met with in- the densest parts of the forest, and at- present can only . be considered as a botanical curiosity. • < . — There are no fewer than 49 clocks oft the. new Cunarder Lusitania. But. the confusion which would result if their hands were uncontrolled is, according ' to the Jewellers' Register,' avoided by Ihe presence of a master clock in the chart "Rouse. As the -vessel goes west all the clock's can be stopped for 20 minutes- at a time- ' To nut them back would, of course, be undesirable When the vessel makes her-re-turn voyage - the hands of the clocks can be simultaneously moved forward, until 'eventually- Greenwich , time, once Again; .prevail*'thrt>6g*W the *sftip. --'/* - r — A fish irhioh ieeds on mosquito larvae is reported from Australia. This fish, known to science as Fseudomugil signjfier,, and popularly known as "bhie^eye," owing to the brilliant blue colour* of its iris> belongs to the- family of aihorinides, a small carnivorous fish found in both ocean and rivers-: ~ The hlue^eye i» a very snjall "fish, about inches long, 'arid is' generally found in shallow water/ ' It is Said that the Italian SoVerhment" is J mucn interested in this m*tt*r, larid la' import ing a number of the-' fish to test their emc%c£ a^'Jaifrj*' &*• fetMyers -fti swatnps anfl t mth^U. ' ['/ — Professor R. L. Garner, who for several years has spent the greater, part, of his time, in .the forests' of Afrjoa, st^dyinar ,ihe lahtfui^e^f mpM&yl' tp^ o^ift; animals. 4 r«pJfei' > to l ithe sUtemente, of Professor W 'T. Hornaday that wild animals in (lie jungle* very rarely ' communicate having learned' ffia*^ r * sflencg,. -.promotes 'vmg'ih&'^MK r fifZ'] Profefeor GSih'er admits that wfld animals are habitually more tociturn than domesticated . ones, <*a are also'' thp'viit^' tribes of human' beings. This lie attributes' to ieck of social intimacies and nomadic habits. But be points out that merely going hunting- and camp: ing in the forest with fire and noise stive* no opportunity for the methodio study of its denizens. It i<* neoesearv to live among them in a state of Nature for an indefinite time. — *A patent has recently been taken out in France by M. Bonnet for a method of obti.'riin<r c«j-bon in an amorphous fused condition. The Apparatus claimed consists of a vessel of bronze or other , metal cor.* tatnirfg two carbon electrodes, "between which n a rod- of pure carbon. Beneath this rod is a smaller Vessel containing carbon bisulphide.; which, when vaporked, will produce a high pressure in the vessel, but will not ,ha.ve>>»ny action upon the carbon. The carboal bitulphids. is first, converted into vapour by means of * slight electric oureent. and as soon as there is a high pressure from this cause a high-tension current is massed through the vessel, with tbe result that in a few moments the carbon rod is fused and eonVarted into the form' of blade diamond. < — Extended experiments recently conducted hare shown clearly that fruit trees suffer very materially, and are often killed* outright, when grass is allowed to grew under the tree and close up to the trunk. Yariotw TKObaMe reasons for "this effect, such as the removal of Dlant food and of water by tbe grass, afco the supposed liberation of carbonic acid, which might prove injurious to the roots ■of the 1 trees; were • respectively 'demonstrated to be outside the primary cause of injury, and. finally, after seven years' work, it was concluded tfcat the injurious effect ■ eonM only iSe -due -to. some poisonous- substance 'formed in' the soil hr the 'roots of the grasa.- On the other hand, it is a well-known fact that in many instances considerable* ' difficulty; *is experienced in obtaining- a growth of ' grass under tree?. —M. de Morgan, the eminent Fren.cn archssoocrist, ■ who has •■been carrying 'on exc*vatk>n* at Stts* within recent years, made a communication to the ' Academic dee Insoriotiona et Belles ILettres upon the rwolts 6* the excavations which yiere undertaken from 1906 to 1907. Some important finds were made in. the recent excavations at Susa. Amon« the objects which were found we may mention especially a status of alaha«ter which dates, , from a period about 4000 B.C. It represents the Emir Manichcsu, and is claimed to be one of the oldest statues found in Asia. At the same meeting M. de Morgan showed a number of specimen* of a very handsome variety of pottery which comes from about the same epoch as the statue. He is of opinion .that this .pottery, together with the prehistoric pottery -of Egvpfc. .is the ancestor of the ceramic art in the Mediterranean region. -, — One would naturally suppose that a loud and, continuous sound could be heard at about, equal dietaries in all directions, in the absence of wind, and if no large •olid body fcrierpoeed. Repeated experi-

fcedts ':have sfaovrij that this is not true, and that "mariners who trust to their ears 'alone when they are on dangerous ooaste guarded by fog signal*, tun a great peril. "Sound shadows"? are 'fpi?£&d, within which (hej^ear <Jetectsf .tip ..-tri^ of the signal, alflpongh "the fog- whistle' may be blowing wj&kirfi^l force, Jf«nd -$ie sound nmj be audibiefraj|ffe mi^^^^d&i^^^KgTj&les,^ audible &gSxk at -tbjfee"' railcs/^ife^Hic& at four miles, fend s^Sttif^-^BW^^&^ntervals, between the-* / audii&f'a*&i*inaiaible points may^be any .<m may also" vary irregulifclj!;. ■ . .thert^re sound"' shadows, the jeßngin_.of r Which -his not been traced, but ijoioh,34oubt3ess,-Ija > c due to some peculiar;*<»aditt6il o/-the aimosphjere. —Science Siftbjge.--.. ' .C* -'-"£ i — Comets 3?|L/Ul^.»uyu«6.^.i#niber^ of, i the solar sya(i§jfl£; > ba^.»>^fax'-a%|»re know/ ! they are al^isSjfrobably .* t&- f l^Hl- masfiive. I This ha« be^iaro^t^isgim^i^-casea 5 by the fact that-jmcto^a'-lEaffiß^,^!^ 836 * 1 t er s^ ccar a plan« > i--'ffe : "a^ri|cfion > <^nas not been prreat er-oug-h 'to inflttenee the planet's motion to any appreciable degree. While the action of the "planet on -the comet may have altered the period of the latter, by several weeks, th& plariefs.rown period; has., not been chained by so much as a single second ; and this proves that the planet's mass must have been at least 100,000 tones as great as comet's. W» hare, thpreforer Hi a conjfit a quantity of material *cry much less than enough to,, make a planet, spread through a voluVno' far greater iiban ' the planet occupies. ' It is therefore csear that it must consist either of^gjajieA.of smsdl densi%f.'Oif of scS«J: partftl«s^ teparjfcad, by empty spaces much larger than themselves. It,i«' probable 'that both tlfese hypotheses *are" correct, ' for the spectral of, oomets show that part of their light is^re- . fleotedr sunlight, <tsch as solid bodies wcfuld send, us, and part comes from bamintous gas— nydtocafbons— giving a series of bri|rht bands identical v.^i^tt- thps» §hov«n. by the > light f*om foe- Base of a candle flame^ or i a. Bunaen Jburiier. , We may thexefors ' re- ' guard a comet as*a swarm of loose particles, - : carrying. with { thejn.morew.or iess gas f . which . 'move together through empty st>ace, simply \ because iher.o> >» «-»o -fe*c«u acting. pull [their, apart strong enough to overbalance [their own Yery -•feeßie gr*fcrfetion. | —Those who lightly think of the duties Jof'^ihe- engineer officer, were ' they- shut - dcsrnr below "with' him and' his 'assistants in that cramped steamy space for even a. few ihomerite aM bre^th^itcVthaJa^iir.j peaking with oil and fat, would alter their entire thoughts of life, and truly say one-half of the world' does noj;, knpw how the othejr lives. The- risks, and.' 'dangers of that steeliined spacer below- water would appal the stoutest hearts if they reflected ; but the senses become dulled by the constant life unider these -cbn&ittons -amonflr "mdvibjr cranks,'. hot air,>- i6l»ttet> oil fut&es, -'4£b«l thfr anxious «ye on the- telegraphs ■from-- -the dc^ck. 'officer.Trßpi looking out Mtvoss "the ' swelling, . health-giving &pve*r.~ .btight.tuttn.,?hine, ...and f)re^, ( breezej^ Ti and l^ i die interest the 3&ok „ owflr ( enjoya 'jxn . hjw, pro'duties.' tte.elefitrio tight ajna a few evil-smelling oil iampg m.dark cdrnera are the suit arid moon of* "wie engineer «<J«wri - belo*. '-'-Tfis very air hW *reat^es iis heated air, and "^ln spite trf- y aH theory and practice in - ventilating 'methods, ' it is a trial for those to live in the pure air oi- heaven* The danger© are y axsa,t : a fingle- fracture in a defective steam-pipe means the end ©f all — a terrible death with pain untold, and beyond any man's imagination. This is .in ordinary oircumstances ; what, then, , must be the conditions in action T Shut' down, with- his whole staff, wider doors oi solid cteel Sin to 4in thick, one' hand on the 'levers which control 'his engines, hie eye on h|» indicators, steam-pressure gauges, aod electric telegraphs, with the crash of thundeiing shot and shell in hie ears, and the vessel reeling with the enemy's hlowi, he cannot- leave oi« post. Happy if he whooonws out of that stifling hole safe and' well after a greatr naval action. All praise to the engineer that inanr would belittle.— "Our -Navy— Past and Present, hw Charles J-, Da jfiacy,- in the Boy/«iO%n Paper, for Octob.eri - - ■> '