SCIENCE and INVENTIONS.

New Zealand Herald, Volume LIX, Issue 18025, 25 February 1922, Page 3 (Supplement)

SCIENCE and INVENTIONS.

"x HEW FLEXIBLE SHAFT. For many small appliances, such as dental drills, horse-clippers, and speedometers, ifc is necessary to use a .flexible shaft between the driving mechanism and the • tool or instrument. An interesting novelty in this type of appliance has been developed in Great Britain. It consists of a steel chain, with alternate pin joints at right angles to each other, the whole mechanism being enclosed in a flexible metallic tuba This tube is filled with grease, so as to lubricate all the joints thoroughly, and - the arrangement is simple, flexible, and highly efficient.

BOAT FOR BATHERS. A new contrivance' for the amusement of bathers is the invention of a Brooklyn man. It is a boat-ahaped float, provided with watertight compartments, at both ends to give it plenty of buoyancy. In the middle of it is a rectangular opening or "well, inside of which the person using it can walk while carrying the float to the water or back again, hand-grips being provided for the purpose. When the boat is afloat a seat is folded down at the back of the well. The bather sits down, and with his hands operates a couple of levers, which cause a waterwheel in front of him to revolve. By this means he is able to propel the float, whijo he steers it with his elbows, which control slide-rods connected with, lines governing a rudder behind.

TALLEST CONCRETE BUILDING. The tallest reinforced concrete building in the United States' is one reoently erected in: New York City.' It stands on.a site approximately 75-feet square and is 18 stories high. From the Dasement to the top of the roof the building measures 223 feet-high. Work was begun in October, 1920,•'and• finished 'early this year. To guard agairisfr freezing the concrete was delivered into the moulds steaming hot, and the moulds were kept sufficiently warm by I means of special heaters. | As one floor was moulded every week, care had to be taken to avoid excessive strains in the green concrete, and five successively completed floors were kept shored, during the greater part of the time. The exterior surfaces of the building consist of white Portland cement and coloured aggregates, including' quartz, feldspar and .green stene chips, the lowest stories being finished by. bush hammering and the 16 umJer stories by the aid of an electrically-driven carborundum grinding machine. The general effect of the surface treatment is said to be excellent.

GLUE MADE PSOM BLOOD. A - new kind of glue, very valuable to cabinetmakers and for various other purposes, is made of dried blood albumin. It is n. dark crystalline substance, and, with the addition of simple chemicals, furnishes the most waterproof glue known. It is" used for airplane parts and " plywood"—the latter term relating to articles which are made by gluing pieces of wood together. Plywood is a great economy, rendering practicable the utilisation of small stuff which used commonly to be thrown away, and thereby saving large-size material. A new and ingenious method of applying the glue for this purpose has been developed by the United States Forest Service. Through a trough of glue solution are drawn board strips of tissue paper, which, being thusi saturated, are then dried. A layer of this tissue paper is placed between two pieces of, wood, and heat is applied with pressure, the result being a joining that is actually stronger than the wood itself. The gluepaper is always ready for use, and it will keep fresh for a long time.

FAST ARMED MOTOR-BOAT. During the war small motor-boats constructed by the British Navy were among the foremost vessels afloat and did extraordinarily good work in hunting submarines and in patrol work generally. Since.the war progress has been made in the design ;and .construction of these vessels. The latest, which has been turned out by ( a British shipyard for a foreign Government, is 55ft. long, with a beam of lift, and a draught of 3ft. 3in. For the sake of lightness and flexibility the vessel is built entirely of wood. It has two skins of mahogany, with a layer of oiled canva3 between them.; A third skin at the foro portion of the boat forms a step of about 3£in. in depth, upon which the vessel rises as she gathers speed, and by means of which she achieves a skimming action over tlio surface of the water. This remarkable vessel, attained an avcrago speed of nearly 48 miles an hour during her official trials, and she carries several 18in. torpedoes, two depth charges, and four macliino-guns. Moreover, she is capable of standing very heavy weather.

GEMS TO SHINE IN DARK. An American has recently patented a, method for making gems shine in the dark. Ho proposes that they shall bo applied' to artificial as well as to natural gems, and an additional and important advantage claimed is that the stones will bo rendered far more brilliant in the daytime Take a diamond, and wt in the bottom part of it a recess to contain, a tiny sealed transparent tube containing a gas under pressure, together with a minute quantity of radium. The radium will make the gas luminous; _ and, if the gas be hydrogen, it will emit red rays. If it bo helium, it win colour the crystal with golden yellow rays. Tho same method of treatment applied to a real' diamond will vastly augment its brilliancy and the stone—as would be the case with the glass imitation—will shine in the dark. I Another idea is'.' to drill one or more holes in the bottom of a real or imitation gem and coat them inside with luminous radium paint. Yet another is to make imitation diamonds of glass through which fine particles of_ gold are distributed. They would not shine in the dark, but would (the inventor claims)* havo a greatly-increased brilliancy in the