Science and Invention.

Alexandra Herald and Central Otago Gazette, Issue 440, 18 August 1904, Page 6

Science and Invention.

PROP. MOSETIG, of Vienna, now fills cavities in bones as satisfactorily as

those in teeth arc filled. He uses a mixture of iodoform, oil of sosame, and spermaceti molted together.

What is called a heat-proof putty is made by mixing burnt lime with linseed-oil and boiling down to the usual consistency of putty and allowing tho plastic mass to spread out in a thin layer to dry in a place where it is not reached by the sun. It can be warmed over a lamp or otherwise for use, and on cooling is hard again.

A doll-maker of Nurcmburg is perfecting a cheap apparatus for making dolls talk, so that even tho very lowest priced ones can utter quaint sayings. It consists of a celluloid strip with a ' record' on it, and a stylus that can be worked by a small handle extending outside .the doll's anatomy, the whole encased in a sounding box. Even in its present stage the idea is a success, but the maker intends to further improve it!

A now journal will -be published shortly in Paris under the name of ' Lc Radium.' It will appear monthly, and its object, as its name indicates, is to give the fullest and latest particulars concerning the developments of that marvellous and mysterious body discovered by M. Curie. The first number is to contain a special article giving full particulars of the scope of the publication and all the possibilities of the wonderful substance that has been named radium.

An important addition to the collection of pro-historic and savage implements preserved in the British Museum has been made by the request of the lato MrTrancis Brent, of Plymouth, who has left the whole of his well-known and extensive ethnological collection to the trustees of tho British Museum, on the understanding that any *«

object not wanted for the national institution should be given to the Plymouth Museum. The Brent collection is rich in palaeolithic implements found in Kent.

An Italian scientist claims to have cstab' lished that electric tramways arc grca* mediums in the disinfection of towns. Ho points out that the electric spark, which is so frequent an occurrence to the overhead trolley, and the emission of light from the car wheel when the rail is used for the return current, transform the oxygen of the air into ozone, which has a purifying and disinfecting influence. The high discharges, he says, are frequent enough to influence greatly the atmospheric constituents, especially where the line passes throughfares. They become antiseptic agents.

The problem of the small enlargement found on the olfactory nerve of carnivora and rodents has recently been solved by microscopic study by M. Joannes Chatin. ' This enlargement,'says 'La Nature,' 'is known as ' the bulb.' It does not constitute a simple swelling of the nerve, but it is a ganglion, in which arc found hot only nerve-cells but also the cells called myelocytes, on whose presence M. Chatin particularly dwells. The existence of these cells in the olfactory bulb, in fact, show that it corresponds to the deeper layers of the retina—an important analogy for the physiology of the sense-organs. SUBMARINE SIGNALLING.

The submarine fog signal of tho late Elisha Gray and Mr A. J.'Mundy has been tried by the Metropolitan Steamship Co., and the officers found they could locate the Boston lightship at a distance of throe miles or more when approaching at the full speed of sixteen knots. The method consists in ringing a submerged bell at the lighthouse by electricity. The sound travels through the water and impinges on two receivers, one on each side of the ship, in connection with a telephone box in the wheelhouse. The observer listens to the telephone and moves a switch to right or left until he ascertains on which side the sound is loudest, that is to say, on which side of the vessel the distant bell lies. By a little manoeuvring the captain can get his direction with accuracy. PEARL CULTIVATION.

It is announced from Paris that Prof. Dubois has found it possible 'to inoculate oysters with the disease of which the pearl is a symptom.' Linuseus persuaded the Swedish Government that by boring a hole through the shell of the river mussel and inserting a grain of sand the animal could be made to secrete a small pearl around it. The experiment was tried, and succeeded so far as to prove the truth of what Linnteus had stated, and to secure him a reward of £460; but the Swedish pearl fishery was soon abandoned. Unlike other gems, the pearl is an organic product, a narcrepus secretion poured out by the pearl-oyster or pearl-mussel to avoid irritation by foreign substance. The Chinose have practised a trick of the Linnoean order for centuries on one of the fresh-water mussels, and have even made the mollusc coat with mother-o'-pearl little images of Buddha. The use of infected germs on the harmless shellfish is new, and its success doubtful. COLOUR PHOTOGRAPH*. A new system of colour photography, by which the inventor says any amateur with any camera can reproduce any scene in natural colours, is announced by John H. Powrio, of Chicago. The process which Mr Powric has perfected has for its foundation a principle discovered in IS6O. Photographs were made in the usual way, but through a fine screen ruled with 300 to 400 lines to the inch. A plate was then prepared with similar lines in red, green, and blue, the primary colours. When the photographic negative, or a positive transparency made from it, was super-imposed on the ' colour screen ' it was found that all colours of the object photographed were accurately reproduced. No practical results were obtained, however, as no cheap way of ruling the colour screen was found. Mr Powrio has' invented a. photo-chemical process, ho claims, by which the lines are laid down on sensitised gelatine. This is then covered with a sensitive emulsion, and there you have the plate ready for use.

A HOME-MADE SPINTHARISCOPE.

Sir William Crookcs invented the instrument which he calls a spinthariscope for the purpose of observing the small luminous particles which radium constantly emits. The spinthariscope is costly, which is the reason why it is used only by a few experimenters. Hugo Licber, of New York city, has devised a similar instrument, which can be very easily made, and which answers the purpose quite well. Mr Lieber explains how anyone may make his own spinthariscope at a cost of about fifty cents. ' Cut a hole about Jin. in diameter in a piece of cardboard; paste this cardboard on a glass plane such as used in microscopic work. Place within tho hole in the cardboard a little mixture of a non-luminous radium preparation with powdered wilomite. Then put a little mucilage on the uncovered side of the cardboard and cover with another glass plane. When this' is placed under a microscope the constant discharge of the radium corpuscles can be easily seen in a darkened room. A sufficient quantity of tho mixture for the purpose can be obtained for five shillings of less.'