SCIENTIFIC ITEMS.

Northland Age, Volume IV, Issue 49, 27 July 1908, Page 8

SCIENTIFIC ITEMS.

. SCIENTIFIC MILKING. V French scientist recently demonthat a cow milked diagonal- > Oia* teat on each side simultaneously— gives utorc and better milk ttwin when one side is first milked, and then the teats on the other side. SAFE WATER-PIPES. in son.*.* of the larger cities of Germany glass water-pipes are used. They are covered with asphalt, to prevent fracture. It is claimed that they give thorough protection afainst moisture in the ground, against the action of acids and alkalies, and that they cannot be penetrated by gases. A “LIGHTNING" WHIP. A whip worked by electricity has been devised by a rural postman. It consists of small copper plates, let into each side of the horse’s collar Trom these a wire leads along the tongue of the vehicle to the waggon itself, whore there is a small battery. All that Is required to set the horse in motion is the pressure qf a button. LUNG TRAINING. . In the Japanese army every soldier Is taught to breathe properly, and with as much systematic care as if he were a professional singer. At the least sign of palpitation of the heart he must cease his exercises and lie on his back to recover. In course of time his heart and lungs become as vigorous and healthy as those of a first-class athlete. THE ELECTROORAPH. A very ingenious instrument is the electrograph. It receives a telephonic , message and writes it down on a record to be used in the phonograph. This will prevent ail danger of misunderstanding, and, if the telephone receiving attendant be absent, the electrograph will take the message for him. When you return to your office you can road off all the messages that arrived whilst you were away. CONCUSSION IN THE AIR. As far back as 1902 “hail shooting” had gained the confidence of vine culturists on the slopes of the Alps to such an extent that the Italian Minister of Agriculture appointed a Commission to inquire into and make conclusive tests of its afficacy. Since then many experiments have been carefully watched, and the Commission reports that (hooting the clouds had absolutely kq good effect, and that protection it the crops against storms must be (ought along wholly different lines. That is to say. bomb firing and the discharge of artillery have proven . powerless to change bad weather for good. MELODY AND THE MUSCLES. . A series of vibrations corresponding to musical tones has been produced as an alternating electric current in certain novel experiments reported by Maurice Dupont to the Paris Academy, Passing these currents through the body may give the effect of hearing the tones themselves, and this has suggested a possible new method for making the deaf to hear. It is further conceived that the currents may be so attuned to nerve cefils as to give either excitation or the reverse—the benumbing being a new kind of anaesthesia. Twenty years ago D’Arsonval reproduced melody and words from a muscle excited by an alternating current coming through a microphone acted on by the human voice. THEN AND NOW. The first submarine telegraph cable was laid by the Bretts across the Straits of Denver in 1849, and consisted of a copper wire encased in guttapercha. It only remained in working order long enough to alflow a few messages to be sent over. In 1851 a cable was laid from the South Foreland to France, and shortly afterwards Ireland was placed in telegraphic communication with England. Other lines followed, and in 1853 the project of laying a cable across the Atlantic began to take practical form. After several failures the task was accomplished, and on August 5, 1858, “England spoke for | the first time electrically with Amerix!a.” As a note of progress it may be mentioned that while on the first cable only six words per minute could be transmitted, the rate is now a hundred per minute. There is now fifteen Atlantic cables, and in all there are some 250,000 miles of cable at the bottom qf the sea. representing a capital of £50,000,000 Sterling. These convey over 6,000000 messages a year. GOOT AND RHEUMATISM : ELECTRICAL TREATMENT. The recent discovery by Professor I d’Arsonval, of the remarkable action ■of high-frequency electrical currents In reducing the pressure of blood in the arteries, seems to promise much Id averting premature old age. Dr. M o*itier seats the patient within a spiral coil of wire charged by an alternating current of 40,000 or 50000 volts with a frequency of 500000 or 600,000 alternations per flocond, a few sittings of five minutes each have considerably reduced the arterial pressure, the cure being permanent and the hardening of the arteries effectively arrested. The rapidity of action is found to vary chiefly with the digestion—not with the patient’s age. Dr. Moutier has successfully treated abnormally low arterial pressure by means of the electric spray or effluvium, a charged t'joetaMic comb forming one electrode f 3ing moved up and down near the spine while the patient—on an insulated seat—grasps the other electrode. In a third form of application, relief is given to gouty and . , rheumatic patients by high-frequency currents conveyed directly to the body through conductors grasped by ihe hands. HOW THE SKY IS COLOURED. Careful observations continued over a long period have shown that the blue of the sky is deepest and dearest in December, January, March, September. Again, the sky is always

most blue at the Zenith, and least ao

at the horizon. So, too, the sky of tropical regions is far more intensely blue than that of the temperate tones.

fcrotesaor Tyndall has shown tnat the blue of the sky is due to the presence of watery vapour, and the more there is of this in the air the paler the blue of the sky will be,> and “vice versa." For this reason, too, the skies of tropical and inland districts being much drier, are therefore much bluer than those of temperate and sea-board countries. MORE POWER FROM GAS ENGINES.

Users of gas engines on a largo scale are commencing to realise that the heat carried away by the exhaust from gas engines amounts to about one-third of the total heat generated, and that the exhaust gases, being at a temperature of about 1,000 deg. F., are capable of raising a large amount of steam, provided that a boiler suitable far the purpose is installed. According to the “Rai'lway and Engineering Review," such boilers are now being placed on the market. They should be placed as near to the engine cylinder as possible, and they consequently form a perfect exhaust silencer When the gases have passed through the boiler they escape, into the atmosphere by a pipe which is free from the usual nuisance of heat and noise. Inasmuch as gas power has not so far been favourably considered in many plants because of the need of the exhaust steam from steam engines for special purposes, there is now a chance for the adoption of the exhaust gas boiler to raise steam for heat' or other purposes, while the motive power is gas, and thus a double measure of economy and usefulness is attained*. In one factory in England these boilers are generating steam from the heat of the gas engine exhaust gases equivalent to the steam generated by 70 tons of coal per week. THE NEW BRITISH BATTLESHIPS.

In the two new battleships which are to be Said down for the British navy in accordance with the current year’s programme, a departure from the policy adopted in regal'd to the armament of the Dreadnought is to be effected. While of the same class and type, they will be 2,000 tons heavier, their displacement being a* bout 20,000 tons. In regard to the main armament, there will not be so many weapons of the larger calibre, though they will be much heavier, a new 13.5-inch weapon which has been severely tested being adopted in the place of the 12-inch. This gun fires a shell weighing 1,250 pounds as compared with the 850-pound shell of the 12-inch arm. Moreover,' a secondary battery of medium quickfiring guns is to be carried, a feature which is entirely absent in the Dreadnought, and which deficiency has been severely criticised. The effect of this modification will be that the new vessels will have an aggregate broadside fire of some 8,500 pounds as compared with 6,800 pounds in the Dreadnought. These two vessels are to be laid down at once at the Portsmouth and Devonport dockyards respectively, and they will each cost over two million pounds. At the present time the armament firms in the country are working at full pressure to deliver the present order of 12-inch guns for the navy's immediate requirements, no less than 120 of these weapons being in course of construction.