SCIENCE NOTES

New Zealand Mail, Issue 1628, 13 May 1903, Page 15

SCIENCE NOTES

THE FLORA OE KRAKATOA

“The island of Krakatoasays “Knowledge,” “lost all its vegetation in the terrible volcanic eruption of August, 1883, which covered the island to a depth varying front one to sixty metres with a bed of red-hot ashes and pumicestone. - Its appearance afterwards was that of a mountain isolated in the sea, rising tvitk almost perpendicular sides to a height of 2500 feet. The island, which is 21 miles from Java and 20 miles from Sumatra was visited by Dr Treub in 18S6. He found it uninhabited, and not easily accessible. On the narrow beach he found fruits or seeds of seven species, of phanerogams, and young plants Of nine species, all the latter, excepting one grass, being the usual littoral plants of tropical islands. In the interior the vegetation was quite different—ferns, both in the number of species and individuals, predominating. Dr. Treub concluded that ferns in such a flora precede and prepare the soil for a phanerogamic vegetation. Their minute spores would be brought long distances by the wind: but it. was remarkable that these would germinate and develop into plants on the intensely arid soil of Krakatoa. A close examination of the ashes and pumice-stone, however, revealed the presence almost everywhere of Algae, coating the soil with a thin gelatinous layer in which the fernspores would find a suitable place for germination. Besides lower cryptogams, Dr. Treub found, in 1886, 15 phanerogams and 11 ferns but in 1897 the flora consisted of 62 species (50 phanerogams and 12 vascular cryptogams) belonging to 24 orders. The ferns still predominated in the interior, and several species of tall grasses formed a striking feature of the vegetation. Seeds or fruits of 30 species were found on the beach, and here and there seedling plants, showing that the seeds were capable of germination. Of the 50 phanerogams, it is estimated that 17 ; were introduced by the agency of tlie wind, 32 by water, and 4 by birds. WHO LIVE LONGEST. Of European nations, the Norwegian and Swedish are longest lived, the Spaniards the shortest. The “Bulletin Generalde de Therapeutique” gives the average duration of life as follows: —Sweden and Norway. 50 years; England, 45 years and 3 months; Belgium. 44 years and 11 months; Switzerland, ’ 44 years and 4 months; France. 43 years and 6 months; Austria, 39 years and 8 months; Prussia and Italy. 39 years; Bavaria, 36 years; Spain. 32 .years and 4 months.—“ Southern California Practitioner.”

A FAMOUS BALLOONIST. Mr Janies Glaisher, F.R.S., for many years Superintendent of the Magnetical and Meteorological Department of the Eoyal Observatory, Greenwich, died recently at the Shola., Heathfield Hoad, Croydon, aged 93. Mr Glaisher made some famous balloon ascents in the interest of science in the years 1862-69. The most famous of these was that made with Mr Coxwell on the sth September. 1862, when the two balloonists made a narrow escape with their lives from the effects of low

temperature and increasing rarefaction of the air. On this occasion a height of seven miles was attained, which remains the highest yet attained by any balloonist. At about 5| miles Mr Glaisker became unconscious, and Mr Coxwell was partially paralysed, being unable to use his hands. The balloon continued to ascend, and death seemed inevitable. Ultimately Mr Coxwell made a desperate effort, seized the valve rope with his teeth, and succeeded in opening the gas escape. The balloon immediately began to descend, and the two aeronauts gradually revived.

DECIMALISING TIME. The.se nations which have adopted a decimal division of money, weights, and measures have not yet applied the system to time, but some of them are proposing to do so. The decimal division of time has been advocated for some years by writers in several French scientific periodicals. A Geneva correspondent of the “Globe” states that a number of manufacturers in tlie Neufchatel canton have already taken to the manufacture of clocks and watches on the decimal system. Chambers of commerce and other trade organisations are also supporting the cnange. The Cantonal Commercial Giiamber of Chaux-le-Fonds has issued a notice calling for models, drawings, and designs for appliances and “works” applicable to the decimal adjustment of clocks and watches with the least possible departure from forms now in use. To decimalise time will not be an easy task. For one thing, the relation between the year and the day cannot be altered, and the number of days in a year cannot be decimalised, but must always remain 365 and] a “bittock.” They may, however, cut up the l day into decimals.

PROTECTIVE DRESS FOR ELECTRIC ENGINEERS. '

The utility and effectiveness of this protective garment has just been demonstrated in the high-tension laboratory of Messrs Siemens and Halske. in Berlin. The protection consists in a • M.rment of fine close brass gauze, which envelops the body entirely, including the uanas, the head, and the feet, so that the current, if it should pass over the body, will only get as far as the metallic surface, and then foe conducted off harmlessly. Among tli© experiments by the person wearing this protective garment was the touching of conduits, carrying an alternating currents of 150,000 volts at 50 periods, and establishing "through his clothing a short circuit between two poles having a tension of 1000 volts causinc a short circuit current of 200 amperes, which was only perceptible to the experimenter by merely a slight sensation of warmth.

SKYSCRAPERS.” Very high buildings in streets are sometimes troublesome to their less lofty neighbours. The great skyscraper known as the “Flatiron” building. New York, has developed the remarkable propensity of smashing windows in shops on the other side of Broadway. The wind is caught by the skyscraper and deflected down and across Broadway with such terrific force as to smash the windows op-

"‘•isite. In order to prevent a recurrence of the strange accident, the owner lias been to fJ-’vidn (?.»<■>fi of bis large _-indows into two by the addition of framework so as to °iv<* (be smaller areas nf glass sufficient strength to withstand the wind, pressure. Trinr? (hat does __ o damage ©offltt©S from the north-east. ~ r ' is a. liigh wtod much felt on the ;ur+>ce but the tall side of the Flatiron hnlluinsyß deflects it with the force of a cyclone

WOMEN WITH BEARDS Two French doctors have been looking into (-be question of bearded women and have discovered that out of everv 1000 sane fonmles 290 are bearded. Of these 230 have only - a slight down, 40 have a very visible beard, and 10 are unmistakably adorned with the hirsute appendage. Out of the 1000 insane women examined, 491 had slight beards, while 56 had beards well grown.

LOW TEMPERATURE STRENGTHENS

SUBSTANCE'S,

In. a recent lecture Professor Dewar referred to the remarkable strength that bodies normally weak possessed when greatly cooled. An iron vessel, which would stand enormous pressure in liquid air, was easily shattered at ordinary temperatures, while lead, which, was so viscous that it could be easily drawn into wire at ordinary temperatures, became intensely hard' when similarly reduced. Even more remarkable was the fact that if a cylinder were fitted with a lubber cap a very slight evacuation only was necessary to burst the latter under ordinary conditions, but at a temperature of minus 250 degrees it was capable of holding the very greatest vacuum yet produced.