SCIENCE SIFTINGS

New Zealand Tablet, 13 April 1922, Page 46

SCIENCE SIFTINGS

I = By "VOLT" "f ■ ~

STEERING BY SOUND. Unusual interest has been aroused by the working of the "radio" piloting cable laid at 'the bottom of the English Channel leading to Portsmouth, which enables fogbound vessels to steer an accurate course into the harbor by means of sound. This cable, which is about 20 miles long, is laid from the entrance to Portsmouth Harbor to the Warner Light on the Channel side of the Isle of Wight. It is beneath the exact course to be followed by vessels, and its "free" end is out at sea. The high-frequency electric current in the cable emits a certain "note" in Morse code. The navigating officer on board a ship wears a set of ordinary wireless telephone receivers. These are connected to a battery, a set of "amplifiers" similar to those used in wireless telephony, and two coils, the latter being hung one over each side of the vessel above the water-line. When approaching the harbor the officer listens first through one coil and then through the other for the "note" of the guiding cable. It may come to him through the starboard coil; if so, he knows his vessel is to the left of tho cable. As soon as ho hears the "note" equally loud through both port and starboard coils, he knows that his ship is directly above the cable, and in the correct channel. A similar cable has been laid in one of the channels of New York Harbor, and these are the only two in use at present. •v A CHANGING WOULD. The tendency of the age is to transfer the burden of the breadwinners for. the masses of the people from the muscles to the nerves (writes Dr. C. T. Hastings in the Health Bulletin). The successful farmer of to-day is the man that is farming with his brain even more than his muscle. The introduction of machinery into all branches, of industry makes life more monotonous. Take, for instance, the manufacture of . the automobile. In many of the factories you will find the men all lined up, every one with a fixed duty to perform when the piece of machinery m passing through reaches him, striking his; blow when the time comes. The man is simply a human, machine working with a monotony that is most irritating; and nerve-racking. In fact, in practically every vocation! stimuli are reaching the brain much more frequently, making more demands on our nerves, hence the lamentable increase in our nervous breakdowns. No one will question the advisability of the introduction of machinery into all industries, but are we making proper provision for nerve relaxation and nerve rest? Are we not adding insult to injury by-crowding our people in the cities instead of laving them live in garden suburbs? The latter can only be accomplished by an efficient transportation service. One frequently hears those who rive gone away for nerve rest boast that they are on the go from morning to night and even get up early to lengthen the day. Your best guide is be temperate in all things/" In fact, intemperance in all things is usually the cause of nervous breakdowns. Make a mental note of this, that any man or woman using their brain and nerves can do more, can accomplish more, in eleven months than he-or she can in twelve; and after middle life it may be that five month's work with one month s relaxation will be the best procedure We have probably few more fitting applications of the proverb that a stitch in time saves nine" than in the conservation of nerve energy. Take no chances. Keep your nerves fit

The sentiment of justice is so natural, so universally acquired by all mankind, that it seems to me independent of all law, all party, all religion.—