SCIENCE and INVENTIONS.

New Zealand Herald, Volume LIII, Issue 16300, 5 August 1916, Page 4 (Supplement)

SCIENCE and INVENTIONS.

RECOVERING QUICKSILVER. The Imperial trade correspondent at Toronto' reports that one of the mining companies at the cobalt mining camp in Northern Ontario has succeeded in making an important recovery of quicksilver by a new process. It is understood that some of the quicksilver recovered by this process has been sold in Canada and a shipment of approximately ten tons lias recently been despatched to the company's office in the United States.

GERMANY'S " WOODEN-TROUSERS."

A medical man named Blumenthal. writing in the Hamburger Xachricbten, alleges that since German import* of cotton came to a standstill the chemical industry has been busily peri men with a scheme to derive from wood a cellulose substance capable of being converted into cloth. Blumenthal claims that the experi- I ments have beeu a complete success, and | that '' to-day .many a man in Germany is running about in trousers manufactured I mainly from materials which not so long \ ago were lately spruce and pine trees in i German lorests." ELECTRICAL DISSIPATION OF FOG. The Smithsonian Institution announces j in its last annual report that it has made j an appropriation to further experiments j ; in the dissipation of fog by elc tririty and that the investigations will he carried out under the general direction of Dr. F. (J. Cert troll, who lias already done much toward the practical precipitation of dust, smoke, and chemical fumes in large industrial establishments. ' According to the Smithsonian report, the essential element to success seems to be some form of electrical apparatus of very high direct j voltage, with facilities for its control and ready application. ADVANTAGES OF MULTI-PLANES. " The eliminating processes of the present war have made the monoplane almostextinct for two reasons, since the speed range need not be sacrificed," states Neil MacCoull. writing for the Aerial Age Weekly. "These reasons are the greater inherent structural advantages provided by the girder-like construction of the biplane and the compactness resulting from the smaller spread required for a given area of wings— matter of importance in landing in restricted places, and in storage and shipment. Both of these reasons must be considered when the spread of the lower wing is made less than the upper, though the advantage of a short lower wing when listing to one side while making a landing should not be overlooked."

ELECTRIC DOOR-CONTROL. An American firm has evolved a motor equipment for the opening and closing of hinged doors by the depressing of push buttons. The apparatus consists of a small motor, which drives a grooved drum through a worm gear, a continuous rope which applies the motor's power to the door, a contractor panel, push buttons, and the necessary accessories. The motor ami contractor equipment is fastened to the ceiling, near the doors which it operates. A three-button control panel is placed at any convenient point. One button opens the door, another closes it. and the remaining one stops it. A limitswitch shuts off the current when the doors are-■• -either completely closed or opened to'flbeir'tull width. It is believed that the equipment will eventually replace the men who ere now employed to open and close doors in packing-houses and warehouses. ELECTRIC STOPWATCH. There has recently been introduced an electrically-operated stop-watch which lends itself to a variety of applications in the fields of industry and sport. The watch is of the conventional split-second type, but the second hand is started by the closing of an electro-magnet circuit instead of by the depressing of a button. The watch may be used in conjunction with a speed counter, in which case the circuit is closed and the second hand started at the. instant the speed indicator begins to rot-ate. Removing the speed indicator from a shaft or pulley opens the -magnet circuit and stops the second hand. Another interesting application cf the new watch is in connection with foot races, in which instance several watches are mounted on a panel and each connected to a device at the end of the respective lanes. 'the watches are all started at the crack of the starter's pistol, but stop individually the moment each runner crosses the tape. CABLES PERFORATED BY BEETLE. A discovery of much importance to telephone and electrical engineers in the United States was recently announced by the general manager of the Santa Barbara Telephone Company. After five vears of persistent effort to determine the cause of mi'iute. holes in the lead armour of aerial telephone cables he established beyond question that the holes are bored by a comparatively small oeetlo with powerful mandibles. For years the telephone company was troubled by short circuits in the aerial cables due to minute holes in the armour, resulting from some unknown cause. Electrical experts who were consulted ridiculed the suggestion that the holes were caused by insects and laid the trouble to electrolysis. Several men who were detailed to travel along the line and watch, for suspicious bugs were soon rewarded for their trouble. They captured a number of bugs in the act of drilling into the lead armour of the cables. Specimens of the bug were sent to Dr. Van Dyke, entomologist at the University of California, who classified them as Siiioxylon declive. a kind of beetle that ordinarily attacks wood, particularly live oak logs or cord wood.

PREMATURE SPECIALISATION. ] in a valuable paper on 'Engineering and Scientific Research," presented to the Society of Engineers in London. Dr. J. A. Fleming pointed out that the great thing to guard against on the part of the student is premature specialisation. He should broaden as much us possible his knowledge of the principles of chemistry, mechanics, physics, mathematics, and metallurgy, and he will then he able later on to buiid up on tlris foundation. Unles.. he does lay this foundation lie will not be able to follow or assist in improvements. As an illustration of this we niav take subjects such as telephony or wireless telegraphy. It is impossible now for anyone to make any really important addition to these subjects who has not a very competent knowledge of physics and some parts of mathematics. The easier problems are worked out and the design of telephonic systems or radio-telegraphic stations has become a matter in which advanced scientific knowledge is an important factor. Then, again." to' make any advance in metallurgy requires a very ultimate acquaintance with the chemistry of metals. A lucky accident might, give a duo to an improvement, but an observer not sufficiently acquainted with modern chemical principles could not take advantage of it or follow it 1111.