SCIENCE AND INVENTIONS.

New Zealand Herald, Volume XLIX, Issue 14906, 3 February 1912, Page 4 (Supplement)

SCIENCE AND INVENTIONS.

ALUNDTJM. Aixndum is an electrically fused alumina, of exceptional purity and great power of resistance to neat, which has lately been produced at Worcester, Massachusetts, for use in making furnaces, and other objects in which a material able to withstand excessive temperatures is required. It is made by calcining . bauxite and fusing it in a water-cooled electric furnace. The less pure products are used for abrasive purposes. Alundum comes from the furnaces m pigs of five tons each, which are crushed and moulded with a refractory bond of a ceramic nature. Attempts to make articles of cast alundum have been only partly successful.

EXPLORING THE DEAD SEA. A German expedition under tho leadership of Dr. Bruhl, of Berlin University, has left Jerusalem in order to exploro the Dead Sea. The work of the party will, it is stated, be purely scientific, and consist of soundings, analysis of the water and minerals there, and examination of the hot-water streams tha>- flow into the sea. Contrary to a long-established belief, it has been proved that fisH exist in certain parts of the Dead Sea, and the expedition will classify them. One feature of the Dead Sea is that its depression is 1312 ft below the sea. level, making it tho lowest spot on the globe.

THE EARTH'S LUMINOUS ENVELOPE. Observers of the sky have noticed from time to time a certain abnormal brightness which cannot be attributed to diffused starlight. Ting is shown by the fact that the brightness diminishes towards the zenith (says the Globe). A notable luminosity has also been observed on cloudy and even foggy nights. The facts of this peculiar luminosity have been long known, and recently they have been an object of special study to "astronomers. And the general conclusion arrived at is that the earth may be surrounded by a permanent aurora, a diffused light analogous in origin to the aurora borealis.

SOURCES OF ARSENIC. The most important sources of the world's supply of arsenic are the silver mines of Saxony, the tin and pyrites mines of England, and the mispickel (arsenical pyrites) mines of Spain and tho Province of Ontario, Canada. The Canadian mispickel contains gold. Germany now produces the greatest quantity of metallic and white arsenic, England, which led the world's production in 1902, having since fallen behind. It is estimated that the United States consumes about half of the entire production of metallic, white, red and yellow arsenic. The yellow arsenic is known as orpiment. In the arts arsenic is used in pyrotechny, and in the manufacture of shot, as well as for medicine and the making of fly-powders.

THE CARAT. The number of persons interested in tho measure of weight called the carat is generally limited by, the. number who are able, or are disposed, to possess precious stones of great value. Of course, it is of the utmost importance to jewellers, and inasmuch as tho slight differences have hitherto existed in the estimation of this delicate weight an effort is being made, particularly under the initiative of Belgium, to bring about the adoption of an international standard carat. The weight proposed is 200 milligrams. It has been customary in English-speaking countries to reckon a carat as equal to 3.2 grains. The uncertainty of the original measure is indicated by the derivation of the word from tfift Qr«*k -word for the fruit of the carob.

AUTOMATIC AEROPLANE GUNS.

The Osaka Mainichi (Japanese newspaper) says that Captain Hino, a Japanese military aviator, is experimenting with an automatic gun of his own invention, which is to be mounted on his aeroplane upon its completion. In &n interview the captain remarked that his motive for the invention of an automatic gun originated during the Russo-Japanese war, when he found an automatic machine gun of Danish type which had been left on the battlefield by the retreating Russians. Captain Hino set to work for the invention of a gun of a similar nature for use on an aeroplane, and the work upon it was successfully concluded about two years ago. The new gun has since been under examination, and small alterations have been been made. It is stated that the automatic gun wil be able to fire 100 bullets a minute.

LURE OF INVENTION. Tho lure of invention is one that influences all people and spares no class or condition of men. From the clergyman in his study to the convict in his lonely cell, it exerts it 3 attraction, and both are found enrolled among the list of patentees, although not so precisely identified. The stimulus is not always the hope of fee or reward, for we find the millionaire as strongly interested as the very poor. There is something in the attraction that cannot be resisted. Someone has said that writing is like flirting. If you cannot do it no one can teach you to do it, and if you can do it no one can keep you from doing it. So it is with invention; no one can teach you to do it, and if you have tho divine afflatus no one can prevent you from exercising it. This is fortunate; for the inventor is subjected many times [to discouraging influences in the first instance. Have you ever noticed, however, the pride with which anyone will display an invention even of the simplest character Surely that is commendable, for we all admire originalitv, and invention is originality, often of the highest order. While the lure may be regarded apart from the results, we 'cannot help realising what a poor world this would be except for the beneficent works of the inventors of all times.

SCIENCE AND ADULTERATION. The progress of science has been utilised not only for the improvement of our food, but also for its adulteration. And year bv year the latter seems to be more skilfully carried out, and more difficult of detection. Hence it seems well to draw attention to some simple tests for the purity of common articles of diet given in a recent issue of the Scientific American. They can be carried out by anyone, and if systematically practised, would probably do more to stamp out fraud than many Acts of Parliament and multitudes of food inspectors. Who in these days knows whether he is eating butter or margarine, or what foreign substances he is getting in his coffee? Here are the simple tests recommended as regards the former. Heat the supposed butter in a spoon over a spirit lamp. Good fresh butter boils quietly, forming a number of small foamy bubbles. Margarine, and most samples of made-up butter, crackle and splutter like green sticks in a fire. Or put the sample in a bottle with warm water to melt for 30 minutes. If the water becomes cloudy if is margarine, if it remains clear it is butter.

NEW POWER-SAVING WHEEL. An invention has just been patented which, if it proves to possess the qualities claimed for it by the maker, Mr. Francis Schraivogel, an Austrian, living at St. Albans, might revolutionise modern methods of transit. The inventor claims that by his system the weight of the load and the resisting force offered by the road are made to assist the motive power. The idea is to construct the axle-centre so that the spokes, inserted diagonally instead of acting directly upon the axle as at present and offering resistance to progress, will help as a driving power when in motion, every spoke in its turn pressing upon the axlecentre, thus propelling it forward. Competent riders have stated that less driving force than usual is required on a bicycle which tho inventor fitted up in this way. With regard to the aeroplane, the inventor believes that his system would put an end to engine troubles. Mr. Schraivogel has also worked out an idea for a gyroscope lifter to be attached horizontally beneath the aeroplane, for the purpose of enabling it to remain stationary in the air if desired.