SCIENCE NOTES.

Otago Daily Times, Issue 12551, 3 January 1903, Page 8

SCIENCE NOTES.

—It is from the United States Weather Bureau that the most emphatic assertion of the relation between Western European climate and a continuous west-to-east' air ; current has come; and of late years the same authority has continually tried to explode ■ a !,n t ,! e J It ' 8 the ' Gulf Stream myth. By the Gulf Stream myth" is meant the belief ■• that this body of water is the responsible factor m modifying tho temperatures of the Western Coasts of Europe; and in examining the grounds for this tradition American, meteorologists havo thrown considerable doubt on the temperatures usually associated with this volurrio of water. The belief in the upper air stream—attributed, to the earth's rotation, or at anyrato modified by it—is, however, of as respectable an antiquity as the Gulf Stream theory. According to the Rev. J. M. Bacon, an aeronaut named John Wise made a statement in 1842 respecting upper" air currents which is pretty generally accepted to-day.. Ho applied to Congress for funds with which to build and equip a balloon sufficiently large to enable him to cross the Atlantio, believing ths,t if he could get high enough the constant wind' would carry him across. "It is now beyond a doubt in my mind established 'that a current from west to cast in the atmosphere is constantly in motion within tho .Veiglit of 12,000 ft above the ocean." Mr Bacon attributes overhead fog or haze to the commingling with the lofty west wind of con- ■ trary lower winds. He notes a curious effect of this overhead haze. "When the fog comes down it often begins with tho down rush of a dense mass, which when viowed; from a lofty building (such as St. Paul's) seems to swamp the lower roofs as with a murky wave. This'jpresently lifts again into space, but only to 'return again and again, until the fog settles down and becomes uniformly denso and general." —The Postmaster-General, the St. James's Gazette understands, has decided to send an engineer to Italy to report upon tho electrical po3t invention of Signor fisoicelli Taeggi. The general conception of. the system, s;iys the inventor, is to have s, small electrio railway mado of steel wires, over which 'light vehicles aro to run at a ' great speed of 250 milos an hour. These wires would be supported by poles.' The ■ wires would bo used as conductors of the current as well as rails, and this current by passing continuously across the'wheels of the vehicle puts in r motion a motor connected with. the/vehicle whioh is drawn alor.g. In all districts there will be special posting boxes and special branch offices, each of them serving the parish or area in which it is situated. At intervals of 'five minutes an empty box starts from the postoffice, and on reaching the first collecting - pole stops there and opens automatically, which movement raises the posting-box inside the column to the collecting box, and the letters are transferred to the latter." As soon as the posting-box is empty it descends, and the colleoting vehicle closes and resumes its journey, performing the same operation at each collecting-box until it reaches, the central post-office again. Tho posting-box does another service. Immediately a letter is dropped into it by a member of tho public it is stamped with the name of the town or district, the date, and the hour. When the letters havo reached the central postoffice they are carried on belts, and so manv dropped in front of each sorter. Once classified the letters are sent off in the various boxes. • < —What is the temperature of tho incandescent gas mantle whei it.is giving outithe greatest amount of light, and how aro its light-giving properties affected by its temperature? The answers which some investigations by Messrs A..H. White and Traver, of Michigan University, supply to these questions contain at least o"ne unexpected factor. The commercial mantle burns under usual conditions at a temnerature between ISOCdeg and IGODdeg. Centigrade; but the luminosity depends inoro on the composition of tho mantle, than on the temperature, and the mantle with tit© highest temperature does not give the most light. The highest luminosity is due to the formation of a soli'l Solution of ceria in thong, and this substance is capable of transforming the heat of the flame into light more economically thai* any other substance yet lanown. .A mantle of pure oxide of thorium was found to be only about one-tenth.as efnoicnt as one with a small percentage of ceria, though the second mantle was heated to a temperature lOOdeg » Centigrado less than the first. A rather ourious property of incandescent mantles • noted by Professor Vernon Harcourt is that they will often' respond to sharp sounds, a3 sensitivo flames do. ' .—Some years ago we drew.attention to the disintegrating powers possessed by 'certain species of bacteria, which attack even the hardest cement with ...success. ' Tho gradual but sure crumbling of the cement used in water reservoirs has been traced to the operation'of countless tiny organisms. ■ The «otion was at first regarded as being ■ due to the solvent property of carbonio.acid ' and other substances commonly present in water. Under the action of the bacteria the cement slowly resolved into soft mud. Tho attack is mado by the übiquitous nitri.fying organism, tho organism which conducts /to a largo extent tho great work of purification throughout nature. The action ceases in tho absence of nkrifiable material, and tho view is that nitrous acid is produced which acts upon the cement lining of the water reservoir. — Experiments on the Erie Canal, although' not absolutely satisfactory, have " sufficiently demonstrated (says the Builder) the benefits that may be ultimately expeoted froni the introduction of electric traction'on . canals. It seems to be quite clear-that the , system should show much greater efficiency than haulage'by horses or mules, and even than steatn-prouclled canal boats, especially when tho natural advantages of America are borne in mind. The new power-house at Niaeara Falls, when completed, will add 50,000-h.p. to tho establishment of the : Niagara Falls Power Co,, giving a total' of 100,000-h.p. for transmission and distribution, with a further possibility of 100.000-lv.p. from the sarno tunnel as a tail ■ race. The power canal passing through the city from Niagara Falls, continues the writer, renders available an additional supply of 10,0C0-h.p. while the completion, of ■'. the plant in progress for. the Canadian rPower , Company "will add 200,000-h.p. more. Altogether 500,000-h.p.i is already in prospect for electrical ipowei' transmission in' the neighbourhood of Niagara Falls, . Western New York, mid Canada. Consequently it is not unlikely that the Erie Canal, in the . United States, and the Wolland Canal, in . Canada, will become large users of electricity for canal haulage. This. agency would undoubtedly increase the carrying * capacity of tho waterways in question,, and ' so encourage a considerable augmentation of ore and coal traffic from tho mining districts bordering tho'Groat'Lakes. —An account is Riven in the American Journal.of Scieneo of a series of experiments now proceeding at Harvard Botanic Gardens, ' on the relations of' electricity to •• plant • growth. Mr A. B. Plowman, in' reporting the experiments, comes to tho general con-, elusion that negative charges stimulate! while positive charges paralyse, the embryonic protoplasm of plants. A similar result was arrived at by Matthews in regard to the effect of positive and negative ions upon the nervous systems of animals. Professor Lcmstrom, of Holsinpfors, has also been carrying out similar experiment/?, but apparently .with a distinctive view to practical utility in. agriculture. He reports that with crops' grown on arable land of medium quality an increase of 45 per cent, was obtained under' the influence of electrical stimulation; but. on poor soil the effect was trifling.' Peas, cabbages, and turnips were affected only | after having been watered, and most plants" were injured if submitted to tho influence of electricity during . hot sunshine. The general concision deduced was that electricity in agriculture could be made to pay. Fifty years ngo this idea was extensively" held, but so far seems nowhere-to have been' acted upon on a laree scale. -.• , — A process has been potented in Germany by G. Bulilmann, of Berlin, for burning off and forming incandescent mantles in one operation. The cotton fabric, impreg-'-' nated with salts of the rare earths, is placed' upon a frame which is exactly of the shape and length, but a trifle smaller in diameter than the finished mantle has to bo. The frame has to he constructed of -wire'gauze, perforated metal, or something of the kind'' and it has a solid top of metal plate.' To the inside of, the. frame is led a gas flame under considerable profsure, or an intensely, hot current of air, which by virtue, of the baffle-plate at the top is made to pass' through the holes of the gansio uniformly all • round from head to foot. Thus the •whole" of the mantle is simultaneously ignited and the decomposition of tho rare earth nitrates ■ and of the cotton fibres takes placo quickly and oveuly nil over tho surface, tho' mantle.. rapidly shrinking in size until it fits tha metal frame. At the same time, or afterwards, a ring-shaned gas-burner, so conntructod as to give an.annular flame, point-' ing downwards, plavs upon the head of tho mantlo, igniting and hardening the supporting collar, etc. Several advantages are • claimed for this arrangement; first, a slow ignition of the fabric and decomposition of' the salts is said ttrbc prejudicial to tho. illuminating power of the compete mantle,; and Buhlmann s process is stated to be speci- ' ally quick in operation. Secondly, when the inranoration is performed by an outside flame, the mantle is only formed in. sections, '• which tends to set up strains in it due to. uneven contraction, whereas the now method, heats the whole mantle at once. Thirdly, the prooess is more automatic than usual', and does not depend so largely upon the personal' skill of the operators, as- all other- ' •nethods do.—English Mechanic ' ,