SCIENCE AND ART.

New Zealand Herald, Volume XXI, Issue 6996, 19 April 1884, Page 4 (Supplement)

SCIENCE AND ART.

A French electrician has invented a new sounding lead, which tells the exact moment of its reaching the bottom, by means of an eleotric alarm bell. • . Dr. Fischer of Trieste, is using cellulose as a dressing for wounds. It is first moistened, and after application is covered with any impervious tissue. Professor Newton says that the earth receives about 3.000,'000,000 of meteors every year, but they only increase the size of the earth one inch in 100,000,000 years, . In Italy the only fast train is the mail train, which goes from Bologna to Brindisi, 472 miles, in fourteen houru fifty-six minutes, which, including three stops, is at the rate of thirty-one and five-tenths miles per hour* The Building News, speaking of the results of the researches of Schliemann, says that the Greek story of Ilion accords with the discoveries of Hiesarlik, and the conclusion is inevitable that the Homeric Troy could have been on no other site. . Dr. L. H. Washington says that when pneumonia attacks the steady, square drinker, one who carries regular his pint to a quart of ■whisky daily, the • treatment comes exclusively under the domain of the undertaker, as the first case of recovery has yet to be reported. A writer in a Boston paper says tnat the family refrigerator contains many of the disease-spreading germs often mistakenly supposed to be in the drain pipe, and he ■fctiinlra that the boards of health in the different cities should make regular inspections of all of them. Hollow steel shafting, which has come very generally into use in Europe even : for such heavy work as steamship propeller shafts, is found to very much lei sen the weight in proportion to the decreased strength. It appears: for example, that a ten-inch shaft with a hole four inohes ip. diameter. has its ■weight reduced 16 per cent, with a loss of only 2;56 per cent of strength. ■ A scheme is being experimented with that promises to be successful, by means of which the problem of economically lighting trains with electricity will be settled. It is proposed to place a dynamo and Willaqs engine on the locomotive, the" boiler of • which will supply steam for working the engine. The electricity generated will be employed in lighting the train with Swan lamps. ■ An eleotric brake is quite a novel idea. It has been invented by M. Achard, a French electrician. The electrioity is obtained by a dynamo-machine worked by the train itself, and can be used for lighting, signals, &c., when worked by the engine. The electric brake has been tried in competition with the Weatinghouse and other systems, and it is said to have come out of the ordeal successfully ; whilst there is a large diminution in friction and wear and tear, as well as economy in coals, all on its side. - A good deal of interest was created two or three years ago by the discovery of small fresh-water medusae, or jelly-fishes, in one of the tanks of the Horticultural-Society of London. They were quite new to science which had only been previously acquainted with marine jelly-fiishes), both as to genus and species,' and it was thought they must have been imported in some way or other from Brazil. Dr.)Bohm, a Prussian geographer, now travelling in the neighbourhood of Lake Tanganyika, in Africa, reports that he has found a species of beautiful fresh-water njedusa in the lake, possessed of a broad, umbrella-shaped disk, and numerous long and prehensile-tentacles. , •Recent investigations into the natural history of the costly phylloxera point to the fact .that the ravages,of this pest are much decreased when the vines are planted- in sandy, soils. The French vines, grafted on American stocks, and plaujed on such soils,. have .been , almost entirely, protected from phylloxera/ This indicates that the indige-: nous ; vines .have- been recruited in native vigour by the grafting process. There is little doubt that, what with interplanting— that is, 'always propogating by_ cutting from the same kind and stock : of vines—and exhaustion from.the soil of all its potash, or nearly so, th 3 old-vineyards have- become so weak,-that they, are immediately, prostrated by. any kind of parasitical attacks, whether of ' parasitic fungi or phylloxera. The best defence is to make such plants as strong and vigorous as we can, by intergrafting, supplying sufficient supplies of manure of the proper sort, containing all the necessary (nineral ' silts as vegetable food--and then we inight let nature have ita way 1