MODERN SCIENCE.

New Zealand Herald, Volume LXII, Issue 18996, 18 April 1925, Page 7 (Supplement)

MODERN SCIENCE.

ITEMS OF INTEREST. FISH AND SENSE OF SMELL. POPULAR IDEA COMBATED. The popular idea that the sense of smell consists of detecting minute traces of gaseous substances in tho air, that tasto consists of detecting substances dissolved in water, and that therefore fish cannot bo said to have a real sense of smell, has been attacked by a prominent German physiologist, Professor Karl von Frisch, of Breslau. Professor von Frisch states that the nerves of tho taste organs of tish, which are located not only in their mouths, but also on oilier widely-scattered spots of their bodies, are connected with quite different nerve trunks, leading to a dilferent part of tho brain, than those of the fishes nostrils. He claims also that tho two groups of organs work differently. Normal fish, said the professor, wore able to detent very faint traces of food flavours which he put into their tanks, and began to hunt about for their dinners; while if ho put their nose-nerves out of commission by a slight operation they were totally indifferent to the "odours," even though their taste nerves were still in i order. In another experiment it was ascertained that the amphibian newts and salamanders used the same organs on land for detecting tho presence of worms underground that they used in the water to find worms that lie had tied up in a bag and dropped into their aquarium. Professor von Frisch therefore concludes that "smelling" serves to detect very minute stimulations, and thus makes it possible for a fish or other aquatic creature to discover food, even at a considerable distance; while "tasting" examines stimulants which are generally more concentrated, at close quarters. HUMAN HAIR FOE BELL. Human hair is employed in tho operation of a new electric fog bell. A strand of several hundred hairs is stretched between two supports, and on tho strand is a link. As tho air gets moist the. hair stretches, the link is lowered and an electrical contact is made which starts the electric motor operating tho bell. NEW COLOUR PHOTOGRAPHY. Natural-coloured pictures with only ono exposure of tho object are possible bv means of a new German invention told of by the Berlin correspondent of tho Journal of Industrial and Engineering Chemistry. Instead of using three exposures of the same object with red, yellow, and blue filters, the same effect is possible by exposing three negatives at the same time with a system of mirrors to reflect the image. The different coloured filters are used in front of tho negatives, and the whole is projected upon specially-prepared gelatine paper. , A naturally coloured print resembling a good three-colour print results. The process is equally successful in portraits, interior views, or landscapes. MAKING NICKEL MALLEABLE. Ordinary commercial nickel, hot or cold, lacks the malleability essential for many purposes. An investigation at the United •States Bureau of Standards has shown that this is duo to tho presence of tiny amounts of sulphur, and that as little as ono part of sulphur in 20,000 is sufficient to spoil the material. This impurity cornes from the ore, which orginally contains more sulphur than nickel. It has been found that manganese and magnesium react with the nickel sulphur compound, and form new compounds with the sulphur. These new compounds—unlike the compouT'd of nickel and sulphur—have a high melting point, and in .addition take the form of uniformly distributed ' particles that lessen malleability very slightly, if at all. FINGER PRINTS INHERITED. Finger prints, the most certain of identification marks, are hereditary. One's distinctive pattern is like that of one's parents, and will be passed on to future generations with relatively little change. These results are announced by Mile. Kris tine Bonnevie, of the Royal Frcderik University, after exhaustive statistical study of tho finger-print records of the Oslo (Norway) Court of Justice, which were put at her disposal. Carrying her researches into lie wider relationships of the human family, Mile. Bonnevie has discovered that th ?re is a resemblance between the finger-print types of related races; the nearer the relationship the closer, the resemblance. Finally, the similarity between the finger-prints of apes follows tho same rule of kinship. SPONGE IRON. " The production of sponge iron, a finelyseparated form of the metal, and very useful in chemical and metallurgical industry, has been made possible on a large scale by researches conducted at Seattle by tho American Bureau of Mines. Tho process depends on the fact that most iron ores are oxides of iron, and that if the oxygen can bo extracted at temperatures so low that the iron does not fuse or run it is left standing as a very fine, porous metallic sponge, presenting very large areas of free surface, on which the reactions of chemical manufacturing processes can take place. The process also promises to render possible the profitable production of iron from low-grade ores and furnace wastc-s. During tho past year a furnace using the new process was operated commercially at Silver City, Utah, producing about three tons of sponge iron daily. AUTOMATIC DISTRESS SIGNALS. A device which sends out distress signals from ships automatically has been invented bv M. Passaquin. a young French engineer. The instrument consists of wheels with projections around the edges corresponding to the signal, "5.0.5.," certain numbers which will give the latitude find longitude of the vessel and the radio call of the ship. An ordinary electric motor operates tho machine, which is mounted on a tabic. Each wheel is set at a proper angle, and the motor started. The signal flashes three times, and then stop l ?. After a short pause tho signal is flashed again and again until the rno'or is forced to stop running. Ships or lifeboats equipped with this new invention do not nave to have radio operators in order to send out messages of distress. A special dial on the transmitter may be set every day with tho exact location of the ship, and the motor turned on to operato the set whenever an emergency arises. ■ RECORD DINOSAUR REMAINS. Word was recently received in London of the discovery of the largest fossil dinosaur bones on record, by an expedition under W. E. Cutler, of tho British Museum, which has for tho past year been working in the dinosaur beds in Tanganyika, formerly German East Africa. The prize find so far uncovered is a shoulder-blade 6ft. 2in. across. The dinosaur beds of Tanganyika were discovered and partly worked by the Germans before the war, and many interesting remains have been found there. There is a close resemblance between the dinosaur fauna of Africa and that of western North America, especially in the case of the Stegosaurs or armoured dinosaurs. Even the newly-discovered giant has American kin, though this particular dinosaur is represented in American finds only by two limli bones. The finding of similar forms of dinosaurs in such widelyseparated regions is a strong indication that climate in the age when these great beasts lived was fairly uniform throughout the world, and that connections existed at one time or another between the various continents.