SCIENCE NOTES

New Zealand Mail, Issue 1651, 21 October 1903, Page 67 (Supplement)

SCIENCE NOTES

One of the "best solutions thus far of the problem of an accumulator for automobiles seems to have been reached in the type of battery known as the “Phoenix.” Instead of plates, cylinders are used for electrodes, and these consist of cores of lead-antimony alloy, •which aro surrounded by the active material of peroxide of lead or spongy lead, the whole being contained in a special sheath of ebonite rings for the negative electrode and of a porous earthenware tube for the positive. The active material is kept in contact with tire supporting lead rods without risk of shaking out. The cylinders are set up in the usual hard rubber jars, and the complete battery is one of the lightest yet produced with an exceptionally large capacity, perfect solidity, and almost-un--1 united life. The sulphuric acid in the jar’s penetrates the porous sheaths without acting upon them.

Stenographic typewritting has been disappointing, but the new “iStenodactyl” of M. Lafaurie, a -French inventor, is claimed to promise very useful —if not revolutionary—-results. It has ten keys, one for each finger, printing on a roll of paper tape. With these keys are rapidly made single characters and combinations representing all ordinary vocal sounds, without regard to spelling, and an operator who ,can write seventy words from dictation on an ordinary typewriter, can write 200 on this machine. The work is easily read after a few hours'’ practice, while an hour’s study a day for four weeks has given a writing speed of 150 words a minute. « « • ® ® Astronomers and amateur observers are still specultaang on the light streaks that radiate so strikingly from some of the lunar craters. It was long ago thought that these streaks—one of which has been traced from Tycho to a distance of 1700 miles —represent gigantic trap-dykes, but Professor W. H. Pickering has more recently suggested that they may be pumice driven out by cas or steam from the volcanoes. £ £ 41 # ■Afore than 200 different types of cells are described by an British electrician, Mr S. R. Bottone, in a new work on galvanic batteries. a 9 An optical screen used in Tyndall’s experiments was transparent only to the heat rays of the spectrum cutting out the ultra-violet as well as all visible rays. For a third of a century, phy-

sicists have been seeking a similar screen that wguM pass only ultra-violet rays, cutting off all others. This discovery—stated to be of great scientific value—has been made at last by Prof. R-. W. Wood, Avho lias been aware for some time that nitrosO-dimethy 1-aniline would exclude all rays except the ultraviolet and some red and violet, but has only just succeeded in obtaining the desired effect by combining this substance with cobalt glass. A remarkable peculiarity of the chemical named is that it gives a spectrum thirty times as broad as that yielded by ordinary quarts. * * « * # An electric lantern is being adopted for automatic signals at street railway crossings in Ledpsie. It - consists of two boxes, one above the other, each having two sides fitted with red glass, and two with green. Cal’s on one line cause the incandescent lamps of the upper box to glow, those of the other line affect the lower box. The arrangement of the coloured glass causes a green signal to indicate a clear track on one read, while a red signal gives warning on the- other road to stop. The lamps being shielded from the sun, the signals are visible in the day time. * » ft a © Doubters stipl insist that the so-called canals of Mars are an optical illusion. A late experimenter, Mr B. W. Dane, made a drawing of the chief markings on the planet, omitting the canals, and when these drawings were copied, by two ladies and two boys from a distance of lOffc. or so, all copies showed canals in the positions given by -Schiaparelli. « * © A. curative effect of vaccination upon whooping cough, first noticed by some .Italian, physicians, has been confirmed by the extended observations of Dr. Dietrio in Algeria. A degree of immunity, moreover, was conferred against the disease. a <* « e 9 Between Bagdad and the Persian Gulf, about 500 miles along the Tigris, is a desert in which Sir William Willoocka finds the same engineering opportunities that are being improved in Egypt-. As late as 870- A. D l ., this land of Chaldea was made one of the most fertile and prosperous centres of agriculture through a great irrigation system, with a main canal 250 miles long, and an immense number of subsidiary canals. For the first ten miles the- great canal, with a width of 65ft, was cut through hard. conglomerate rock to a depth of 60ft. With' neglect of the works, the main stream of the Tigris became diverted, the cild bed of the river silted up, the irrigation system fell into ruins, and

only mounds on he barren plain mark tbo sites of the ancient villages. To veqlaim nearly three million acres by a new irrigation system is Sir William’s hope.

The freezing of leaves and buds on clear spring nights, when the air temperature is above freezing point, bas been supens>titiousiy -looked upon as an effect of the moon’s light. A British expei-imeuter finds that, while all objects have the temperature of the surrounding air on cloudy nights, rapid radiation may produce a difference on clear nights, and a piece of cotton proved to be at times 6deg and even Bdeg colder than the air. Plants may be similarly chilled below freezing, with the air above. « <» • « » Pointing out the need for protecting egrets, or white herons, a British naturalist cal,ls attention to the possibilities of egret-farming. This has been successfully established at Tunis, and as egret-plumes are worth more than their weight in gold, the profits from cutting the feathers from the birds should be large. a w « * # Certain balloon explosions are attributed by W. ds Fonvielle to electric sparks as the aai-cn-aui grasps the valve rope. The use of gloves in stormy weather is suggested. « « « » # The general circulation of the atmosphere has been outlined from a late report by Hilde-bran d-sson, the Ups a la meteorologist. Above the thermal equator, and constant throughout the year, is an eastern current, which carried the dust of the Krakatoa eruption of 1883 around the world from east to west in twelve to thirteen days, showing an average velocity of 37 metres per second. Above the region of trade winds is an upper contra-trade wind current, from the south-west in the northern hemisphere, and the northwest in the southern hemisphere. The contra-trade wind current gradually deviates untijl it becomes a western current above the -barometric maximum of the tropics, and at the crest iof this high pressure it descends to feed the trade winds. Near the equator are regions belonging to the belt of equatorial calms at one part of the year, and to the trade winds at another, with a corresponding overlying monsoon extending the contra-trade wind in winter and the equateriqjl eastern current in summer. The high pressure of the tropics steadily diminishes toward the p,-les, and the air of the temperate zones is drawn into a vast polar whirlpool tur-niirg from west to east, the circular movement reaching

upward at least ten or eleven miles# The influence of suit ace irregularities mostly disappear at the height of the# lower or intermediate qlouds.