SCIENCE NOTES.

Otago Witness, Issue 2650, 28 December 1904, Page 68

SCIENCE NOTES.

| — Professor- JLoeb is alleged to"have stated ;»t St. Louis, -where the International Con'igress'' of ' Scientists has been ' meeting, that are jipw /sufficiently aflyaneed . in. 4£beir .science to^-be-abJe' to control the sex r of JQewJy-formed cells, -and of saying whether' or 'not the newly-generated body ' shall be male or female. ' The" professor's name occupies an honourable' place- in the roll of American scientists, and any '-.announcement 'be makes is received generally with great respect. For thisjeason, the New York'corres--ipondent of the: London Daily Telegraph; sought out several biological experts in New (York,' andaskecLtheir views on' the preblein which Professor ' Sohenck failed to solve. jWith one accord they refused'"to express ' a 'definite opinion on Professor Loeb's alleged fctateiuent until ''a! --full report of his actual words had been . -given. _ Those who' con-, pented to speak," while' declining to give^ the authority of their names, said the state- ' ment was apparently incredible. Several discussed- Prof essor Sehenck's investigation of the same problem, with the 'object of" showing hgw little is actually known of Ahe subject. Professor Schenek really died a victim of ,his> delusion that the diet "of the parents was the mam_determining cause )of the sex"_o£' the child. "To quote one expert: — "In the future all" things are pos- j : sible, but so far as the prssent state of j knowledge goes there is nothing to warrant j -the idea ,hat the* determining of sex is . 'humanly possible.^ * For all"" practical pur- j poses the old ■ housewife who recommended; , filer daughter to " tie H piece of *wool on (her left little -finger to * secure a boy and jon her right Jittle finger to secure a girl knew jas : much as we^do regarding the real' point j *t- "issue. .ha's certainly been xnade.l in. biological- study/ but much- more is re^ iquired before we '"can solve" the sex problem, of humanity, which has defied the students of .-alt-ages.*' ' r*- " -^ —"The art jpi taxidermy seems to be just Bow 'undergoing a change, and a ifor^'the better. -From an artistic standpoint a "stuffed" ' animal is not a thing »f beauty as a rule, and to cannot imagine^ any painter venturing to use one for a taodel. - "Stuffed" is a most proper term Kxj apply to many of these travesties of nature, for they appear to be stuffed' to Repletion; with every trace of beauty removed in the process. There are, of pourse, exceptions in-the case of those persons who have earned a name for executing such wort with anatomical and artistic knowledge. The -work is now being carried Out at one of the transatlantic museums With consummate skill, and the whole jpro--joess is described and illustrated in a recent issue of the Scientific American. First of Jfcll the sikull, pelvis," and legs of the animal Ere set up on.-a kind of framework to represent the skeleton. Next, this frame,work has the muscles built over it incnodelling clay by a skilled sculptor. At Various times during the process of buildjbig ■ up, the skin,, which has been duly is tried onto the' limbs. Eventually, a mould is made from the built-up foim, and from this a cast is produced, the original model being discarded entirely. *Thus in the finished animal no part of the jtciual .cr&aj&rei is-' used except the skin. -, . I return 7 home " af-ter^-f our months' absence^* sifc* v down' at my\ desk '-(writes "CJ;f.; SV- in the" Pall Mall Gazette),- and pick up- my .^spinthariscope. I put "it. to •ny, eye, and there is the dance of the elec- j trdps and the shimmer of their flight, as 3 active as when I last saw it. Yet the spinthariscope has been lying in the dark untouched', in an unheated room, all these months, and I remember that physicists are in doubt as to whether four or five ! ]6gures can express the number of years ; for which this process will continue. This,J 'of course, one is. familiar -with, on paper ; but to pick up a spinthariscope, after four months, and realise that the shower of , '•parks has been continuing all that time.

Nclajr and nighty without 'a second's intermission, is-- to obtain" ar fresh, appreciation of - J wfiat . radium is teaching us. Radioactivity, by-Jthe.- way, ' is not the power of %ivinff-. I ,off _rays. - Otherwise a ' gas-jet is or "a warm /-kettle, oorr r .'indeed, -things^. all' and' sundry ►" The . power /of; producing^ jr-raysjis^not-^radio-activity, and 'there is n<>' evidence -as'" yet" 1 to "show, that the human, body is radio-active,' though a leading- medical journal -'-Has* 1 been "misled* by the term. Radio-activity is a symptom "of atomic evolution. - ' - " ■'- ' '— A writer in the November World's „ "Work, describing Sir Oliver^ lsodge's - experiments in dispelling fog by . electricity, says, it remains now for some of theglarge enterprising shipping or railway companies to undertake a "really practical tsst on a large scale: — "Large sums of money are spent yearly by the railway companies on detonators^ extra signalmen, 'foggers,' and to thi9 is' added the expense and inconvenience of trains-- delayed by fogs.'- Surely Lit .would be cheaper and simpler to dis- ' perse the fogs, even if it were only for a (comparatively small area around the railway stations." - The , apparatus, is urged, might also be employed with ad- , vantage oh~vessels or in harbours, in lighthouses, lightships,- rivers, and other places where natural fogs accumulate. London fogs ' and aft town fogs, ifc is pointed out, are artificial, >in that they can be prej vented if the public would take the trouble jto burn their coal completely, and not I jvaste more than half by discharging it into . the air in the form of smoke and soot." I —The earfh is nevex really still. Ii , quivers 'and throbs and warps and bends night and day (according to the Alining Reporter), and even in the absence of all merely local agencies that can be detected, j Not only is this the case on the surface, | btiir it is the same when - a position in a 'mine is taken: v Thjs instability' of the ■ea'rtli ' 01 the constancy of its tremors is attributed to causes directly the" 1 varying intensities* of atmospheric and oceanic pressures.' The placing of a. great weight — as a mountain,-rfor — on any portion of the > surface will naturally ' tend' to produce a depression of the surface at that point, and consequently movement;, but it was probably never imagined until now that when the barometer rises an .inch, over land area like- that of Australia, the increased' load of air * sinks the entire continent 2in or 3in below the normal level. Over a like sea area, the water j surface may be depressed a foot or more. Thus, as the mass of air sweeps in wind I or creeps by slower convection from place to place, the yielding earth sways up and down beneath its weight. The increased accumulation of air ovei a given locality is found to influence the pendulum in the manne* of (although, of course, to a much less extent) a solid mass, as a mountain. The tides exercise a, disturbing power similar to that of the atmosphere ; thus, the heaping waters of the flooc 1 ' depresses the shore, whereas the ebb permits it to rise again. — The use of suction apparatus for household cleaning is now so general that it no longer arouses comment. A form of apparatus in which the same principle is Involved has recently been brought out in Paris, aud will doubtless prove of interest, although the principle is not new. The contrivance in question is a portable pneumatic duster, consisting of a bellows ?onstruoted somewhat after the fashion of an accordeon. From the bellows a tube leads, iby which an ordinary duster is carried, j "Within the bellows packing material is contained which retains the dust gathered 1 . The duster is passed over the object to be cleaned in the ordinary way, and the dust which is displaced "is drawn into the | tube by operating the bellows. As soon ;as the dust is caught by the packing ' material, it cannot be discharged by compressing the bellows. When the packing is quite full of dust, it is taken out and , thrown away, and new packing is inserted. — Scientific American.,

— Mr H. Nagaoki, whose letter 13 dated from the Physical Laboratory of tho Imperial University, Tokio, writes to Nature to describe a characteristically ingenious method of making perceptible the minute variations in the length of a bar of metal which has been magnetised. Professor Joule, indeed, said that the change of length induced' by magnetising a wire, though very minute, "Avas so rapid that it could be felt by the touch. But not everyone has so"* acute a sense of touch as to be able to feei an elongaion amounting to something less than the one-hundred-thousandth part of an inch ; and the demonstration of the effect to a class has remained for many years distinctly wanting. But-- Mr Nagaokis method is beautifully simple. Over the surface of a liquid there are constantly passing minute ripples, which move so fast that they elude the eye. They are very tiny, and are quite distinct from the ripples that one can see, being, in fact, not caused by any movements of -the body of the liquid, but by shivers of what is called tho sfcin or the "surface tension" of the liquid. They are usually called capillary ripples. Professor O. V. Boys, who hit on a method of making them visible by illuminating the liquid for very small fractions of a second only, called them invisible: ripples. The slightest disturbance of the surface film of the water will produce them. Mr Nagaoki therefore suspends his steel bar so as just to touch, or as just to fail to touch, the liquid— a pool of mercury is the best for the purpose. When the bar is magnetised it elongates slightly, disturbs the mercury's, surface, and forms the> fine capillary ripples.