SCIENTIFIC.

Otago Witness, Issue 1891, 1 May 1890, Page 35

SCIENTIFIC.

— A recent telegraphic dispatch to the Chronicle describes a new device just announced by Mr Edison, which consists of a combination of the phonograph and camera by which a speaker, in full action and gesticulation before the combined instrument, may have his speech conveyed by the phonograph, while the camera conveys his bodily presence, action, and gesticulation to a distant quarter, where it is reproduced and shown upon a screen. The idea was suggested to Mr Edison that if a rifle ball could be so photographed as to show the bullet as if at rest in its swift passage, with the condensation of air in its front, a vacuum behind, and air eddies in its course, it would be possible to photograph a speaker as manytimes in a second as would be required to | keep him in all his motions direci.ly before I the eyes of an audience, the successive I photographs being conveyed, as rapidly as produced, upon a distant screen. The close of the dispatch reads as follows :— He thought that if a speaker's personality could be brought before the eye by means of photography and a stereopticon while the phonograph was bringing the subject matter before the ear, an important end wou'd be gained, and to accomplish this experiments were planned and carried out. The result has been a marvellous success. Imagine a popular lecturer, preacher, or orator delivering an address. In front of him, at a socalled reporter's table, are two small machines, one the well-known phonograph and the other an ingenious piece of mechanism by which photograps of the speaker are taken in succession with enormous rapidity at intervals of from one-eighth to one-twentieth of a second. And suppose both of these machines are at work silently recording both the uttered speech and the personal appearance of the speaker. The results thus obtained may be sent to any desired point and thrown on a screen by in. ingeniously contrived piece of mechanism. Thus the exact appearance of a speaker, with all his gestures and plays of features, arc reproduced, while the phonograph simultaneously delivers his speech. The interval between successive photographs is so infinitesimal that even the picture is an apparently living one, moving, gesticulating, and uttering words in fact spoken by the phonograph. The greatest difficulty experienced by Edison in his experiments was the synchronization of the two instruments so that the utterances of the phonograph should exactly coincide with the gesticulation, but this was finally overcome and the experiments were crowned with the most perfect success. Edison is not pushing the matter at present, being absorbed in his experiments on electrical traction for street cars. When that problem is decided he may bring this new invention prominently before the public. — Chauveau has been extending his experiments, which prove that the microbes of some infectious diseases can by treatment with compressed oxygen be deprived almost entirely of their harmful properties and yet retain their vaccinal properties almost unimpaired. Of course people have long been familiar with the similar fact in the ordinary experience that vaccination gives a security against smallpox almost as well as a survived attack ot the disease itself, but it is hopeful to have further decided evidence in other cases. # — The storage battery harnessed to the windmill is sure to become of great service in driving the machinery of future generations. Before very long more attention will have to be given to the yoking of the winds, waves and tides to the driving-shafts of our industrial works to supplement the storage reservoirs of the coal mines. —A new industry in artificially cultivated sponge is in process of creation. M. Oscar Schmidt, professor at the University of Gratz, in Styria, has invented a method by which pieces of living sponge are broken off and planted in a favorable spot. From very small cuttings of this kind Prof essor Schmidt has obtained large sponges in the course of three years at a very small expense. One of hia experiments gave the result that the cultivation of 4000 sponges had not cost more than 225 francs, including the interest for three years on the capital expended. The AustroHungarian Government has been so much struck with the importance of these experiments that it has officially authorised the protection of this new industry on the coast of Dalmatia. — Schiaparelli, the Italian astronomer, has made a surprising discovery that the planet Mercury revolves on its axis in the same time as it makes one turn round the sun, about 88 of our days, so that in Mercury the day is identical with the year ; an important fact is that the behaviour of the moon relatively to the earth is the same aa that of Mercury to the sun, the moon turning once round its own axis in the month. The varieties of climate in Mercury must be something remarkable, one half of it in perpetual day and the other in perpetual night ; the one half is perpetual summer, probably fiercer than anything we know, and the other half in cold, compared to which our Arctic regions are tropical. The only portions of Mercury habitable from an earthly point of view would be a circular belt between fche very hot and the very cold. Up to the present it was supposed that Mercury had the | same day as the earth, but accurate enough observations have only recently become possible. — Zercon is a metal not found pure. In fact, no use for the pure metal has ever been found, therefore it has not been reduced. An oxide of this metal called zerconia is the most infusible of all the known oxides. The oxide is reduced to a fine powder. A common cotton wick is thoroughly filled wiih tlie powrlered oxide, then Hie cotton is burned out. The wick is all consumed excepting lt thin, delicate, snow-whito oluum ut "i! t e zerconia, which is left exactly the shape of the wick. As the burning gas impinges, upon this column of oxide, the latter becomes heated white hot and glows with a soft incandescence, second only to the electric light.^ A mechanic may not know the name of this burner from the above description, but it is named the welsback, and by that name will be readily recognised. (Continued on page 87. j