SCIENCE NOTES.

Otago Witness, Issue 2813, 12 February 1908, Page 76

SCIENCE NOTES.

—An Austrian electrician claims to possess an inventioa which he says wjll Nullify wireless messages in war time. The Jiventoi declares that the apparatus makes )n intelligible all messages sent within a Sidius of 700 miles. The mechanism is Yirto simple, consisting of a revolving jwer with 10 or more batteries, which send flashes varying- in strength. The radius is stated to be so deluged that the operators will not be abie to distinguish one message from another.

— Anthropologists have remarked that taking aim is a human characteristic thai )ven the anthropoid apes cannot be said to nare. Apes and monkeys frequently throw nuts and 1 sticks, sometimes with unpleasant consequences to others ; but they show little or no ability to take accurate aim. The baboon is said to exoel somewhat in this >espect ; but still it would never pass for a marksman. Accuracy of eye and the judgment of- direction and distance that *ro involved in real aiming have been dereloped only by man, and are among the tokens of his intellectual superiority. — The annual Huxley lecture was delivered this year by Professor J. J. Thomlon. The subject of the lecture was "The Influence of Recent Discoveries in Electricity on our Conceptions of Matter and Ether." Towards the close of the lecture Professor Thomson referred to radium, which, he said, possessed an enormous imount of energy, but was very stingy in riving it out. Radium never gave up any mergy except on its death bed. The only ?axes it paid were the death duties. When people talked about the possibility of going across the Atlantic with a pinch of radium as the motive power, they forgot the voyage would take about 2000 years, considering the time radium took to give out its energy. — Professor Otto N. Witt, of Charlottenburs:, now asserts that the latest experimenvs of Professor Ramsay show that under the influence of the energy contained in radium emanations, well-known elements like copper can now be converted into others just as well known. This proves that the ancient alchemists were on the right track. Four years ago Professor Ramsay 'discovered that radium emanations changed to helium, and, later, that this is the source of all the inactive elements. Latterly Professor Boltwood, of Yale, has shown that a new element exists in the uranium minerals, where radium is found, and which is the parent of radium. This new element gives off both alpha and beta radiations, produces no emanations, and resemble; thorium. lonium is the name proposed for this substance. — A novel project , has been conceived (sayr the Pall Mall Gazette) by the celebrated Arctic explorer, Captain Ronald Amurdsen, the Norwegian pioneer, who four years ago discovered that North-west Passage which had been vainly sought .Turing four centuries. The captain now proposes to set out on an expedition for the North Pole; but his idea is to utilise bears instead of trusting, like previous explorers, to dogs. He has formulated a plan of route, entering the Arctic Sea by the Behring Strait, and then drifting northward with the Nippon current till near enough to make a dash for the Pole. The route thus proposed coincides with that taken by the ill-fated Jeanette. Captain Amundsen's vessel will be equipped for a stay of six years in the Arctic. He will take on board six sledges. The novel feature of the expedition will be a team of six polar bears. These are being trained in Norway by the well-known, professional trainer Herr Karl Hagenbeck, who is teaching them to drag sledges with the most promising prospects of success, unlikely though such an attempt might seem to be of satisfactory itccomplishment.' The captain believes that these apparently intractable animals will prove as docile as oxen, and that, being inured to the intense cold of the Arctic, they will be more serviceable than the 'dogs hitherto ' used, "as they have immense strength and endurance. — What is the solidest thing in existence? It is not (says Science Siftings) iron, it is not lead, it is not gold, it is not platinum, it is not any of the things that impress our sense as being extremely dense *nd soli*. The answer, as recently given by Sir Oliver iodge, is amazing beyond belief. The solid«st thing in existence, he avers, is the very Jthing which for generations bias been universally regarded as the lightest, the most impercagtible, the most utterly tenuous and evaneswnt beyond all definition or computation— the ether ! 3*he ether is supposed to pervade everything, to I?e everywhere, to penetrate all objects, to extend throughout all space. The earth moves through it and it through Jhe earth; the sun and all the stars have their being and their motions in and through ether; it carries light and electricity and all forms of radiation. Nobody has •yen seen it or rendered it evident to touch or to any other sense. It escapes all efforts to feel it, to weigh it, to subject it to any kind of scientific experiment. It plays -no part in mechanics. It neither adds to nor takes awaj from the width or substance of any known matter. And yet we are now assured by some of th« highest authorities of science that ether is millions of - times— Sir Oliver Lodge says "50,000,000,000,000 times" — more dense than platinum, one of the solidest metals known ! —Mr Tesla announces- that, with the coopezation of power-producing companies at Niagara Falls, he is preparing to hail Mars with Niagara's voice. A way ha^ been found at last, it is asserted, for transteitting a wireless message across the gulf which Separates this earth from Mars •Onae that has been accomplished, *ncl Mars— which is considerably older and supposedly mote advanced in science than us— fcas acknowledged the rpceipt of our signal, and sent back fiaeb for iasb, it will remain *o devise an interplanetary code through 'the medium of which the scientists of this world and of Mars will be able to understand what each la saying to the other. Mr Tesla has been . quietly working for several years an » wireless pow«r plant feapable of transmitting 10,000 h.p. to any part of the wodd, or to any qf x)ur ■ neightouring planets*, -for that master. The mere ma^er of distance between despatching and receiving points is absolutely no object whatever. power, Mr ffeula Bays, may TSb sent one million or more miles just as easily as one mile. Beverai pf the power companies With immense generating plants at Niagara falls have agreed to co-operate with Mr esla in an effort to reach Mars by wireless Bower. These Niagara power plants, Mr Tesla Beolares, ara now capable of producing •lootrioal vibrations of suoh intensity that, II measured *CQPrdip* to ordinary stsui-

dards, the rate at which their energy is delivered could readily be advanced to a billion horse-power. But no such performance is necessary to produce strong electric currents sufficient to reach Mars. A few hundred millions horse-power will be quite enough. Mr Tesla has no doubt there are people on Mars ready to receive his signals. He believes from some mysterious electric movements he has detected floating about for some years back that the Martians have been signalling to us.

— One of the most dangerous of all explosives is a black powder called iodide of nitrogen. When it is dry the slightest touch will often cause it to explode with great violence. There appears to be a certain rate of vibration which this compound cannot resist. In expeiiments to determine the caus^ of its extreme explosiveness, some damp iodide of nitrogen -eras rubbed on the strings of a brass \iol. It is> known, that the strings of such an instrument wi'! vibrate when those of a similar instrument, having an equal tension, are played upon. In this case, after the explosne had become thoroughly dry upon the strings, another brass viol was brought near anrl the strings sounded. At a certain note the iodide of nitrogen on the prepared instrument explcded. It was found that the explosion occuricd only when a rate of vibration of sixty .1 second was communicated to the prepared strings. Vibration of the G string caused an explosion, while that of the E string had no effect.

— The bric-a-brac shopkeepers Jacob and John Watkins Brett were the first to deal with submarine telegraphy from a public and coirmercial standpoint. One Juno 16, 1845, they registered a company for the purpose of telegraphic communication between England and France: and a little later they addressed themselves to the Prime Minister, Sir Robert. Peel, who did not, unfortunately, share their confidence This move, indeed, only involved the Brotts in a depaitmental coi-respondence — mor© academic than useful — 'in which they were diplomatically passed backwards and forwards from one Government office to another. By 1849, however, the Bretts had obtained consent from the authorities of both countries to lav a cable across the Strait of Dover- The laying- of this line was from the Goliath — a small Thames tug with a very big name ! The line only consisted of gutta-percha^covered copper wire. This was unwound across the Channee from the huge reel on the deck, and the further end connected to a, Cooke and Wheatstone needle telegraph instrument set up in a. bathing- machine. The carrying out of this enterprise excited little or no atention at the time. It was, indeed, looked upon as a mad 1 freak — and even as a' gigantic swindle — indulged in only by wild minds. When accomplished, The Times remarked, in the words of Shakespeare, "The jest of yesterday has become the fact of to-day." But a few hours afterwards it might with equal truth have been said, "The fact of yesterday has become the jest of to-day !" Messages were, however, certainly sent through this insulated wire. Brett had a document signed by 20 Frenchmen, dated September 6, 1850. who declared that they had seen the electric telegraph working between France and England. The signals, it must be confessed, i were rather incoherent ; the operators at each end blamed those at the other, and tauntingly suggested that the excitement, or something else, must have gone to their heads. In any case, the glory of this telegraph was, unfortunately, short-lived, for after the first evening it maintained a-n. obstinate reserve, and never srjoke again. An attempt was then made to raise the wire, but as a leaden weight had 1 been attached at every .hundred yards in order that it might be successfully sunk, all efforts were in vain. However, a considerablelength was brought up by a fisherman in his trawi, who carried it oft to Boulogne in triumph as a piece o f rare seaweed with a pith of gold ! Then, again, on December 19. 1850, a concession was granted to Jacob Brett by fie French Government, and on the strength of this the Submarine Telegraph Company was formed. But £3000 was all the public would subscribe, because it had been pioved that submarine telegraphy was an impossibility ! Yet these early pioneer-a, with that peculiar obstinacy that characterises inventors, went on believing in their own ideas. Mr Orampton, the well-known railway engineer, came to the rescue with £7500 of his own and a similar amount from his friends. Then Mr Kuper, a colliery engineer, came along and baid : "Why not protect your gutta-percha covering by an iron sheathing?" Well, the cable, with its iron sheathing, was made, and on September 25. 1851. a procession. with a man-o'-vvar to l&atl the w»v. started 1 from the South Foreland to the shores of France. AH went well until they were in sight of the opposite coast, when the coble gave out. Another mile was ordered, manufactured, and laid, and on November 13, 1851. the public sent a message through a submarine cable for the first time in the bistorv of the > world.— Chas. Bright, F.R.S.E., in the Magazine of Commerce.