Scientific Puzzles.

New Zealand Tablet, Volume XXX, Issue 27, 3 July 1902, Page 20

Scientific Puzzles.

A CERTAIN man (says the New York Press), who has since made a reputation as a journalist and author in this city, never could make much progress as a youth in chemistry because he wanted to know ' why.' When he saw the professor mix oxygen and hydrogen and produce water he demanded to know why this result, and as no one could tell him he became discouraged. As a matter of faot, a large portion of our scientific knowledge |is purely empirical. The knowledge derived from the observation of phenomena, from experience and experiments, enables us to accomplish wonderful things, but there our knowledge sticks. The world is full of 'undiscovered discoveries.' It is now six years since Professor Ropntgen passed his new light rays through wood, paper, and flesh, but to this day no one. understands why these rays act as they do At first f-ome scientists fell back in desp dr on thu old theory of light, which was that a radiant substance gave off light as a flower does scent ; but as that theory has been totally exploded the rays are as great a mystery as ever ; in fact, the more we try to learn about them the more mysterious they become. Then there are the V rays, by which their disco\erer, Alexander Orloff, has steered a torpedo at a distance of two and a half miles with no connecting medium but the air and the water. The Y-rays are as great a mystery as the X-rays, and, as if those were not enough, along comes the Polish scientist, Cuire, with his Becquerel rays, which he obtained as the reanlt of experiment and which puzzled nobody more than their discoverer. A substance called radium, which Cuire discovered, can be made to act as a sort of mineral glow-worm. It will store up sunlight, and even if kept for five years in a pitch dark place, will give off light at the end of that time. As radium costs 10s an ounce to prepare, this sort of perpetual lamp is not likely to become popular, however. Take a lump of loaf sugar and spin it rapidly on a turning lathe, tapping it gently the while with a small hammer. The result will be a constant display of light. Why ? Nobody knows. Then there is that s-centific wonder, the spectroscope, an instrument made of glass prisms. Iron, gold — each different element — produces a different dark line across the rainbow-like play of colors into which the prisms divide the white light, and we thus are able to know the composition of the sun. moon, and stars. We know by experiment that the different lines will be foand in the spectrum and that they are caused by interference of rays. But why do these various substances produce these various rays ? Again nobody knows. We are so accustomed to the compass that we forget what a wonderful thing it ie and how little we know of it. Thb greatest scientist to-day knows scarcely more about why the compass aota as it does than did the first man who used it ' in the early dusk and dawn of time.' We have discovered that a magnetised piece of steel, swung on a pivot, will, as a rule, point in a certain direction. Why it does so is not known for certain, and perhaps never will be, though any number of ingenious and learned theories have been advanced. In some parts of the world tne compass points due north, and in others it points to the east or to the west of north. And in some parts it will not act at all. At a place called Kotchetowka, in Russia, Professor Leyst, of Moscow, found that the needle pointed downward, just as it does at the magnetic pole. And yet there is no iron within 600 feet of the surface of the earth of that place. The whole subject of magnetism and electricity is full of miracles and mysteries. It is not so long ago that the school textbooks used to start their little chapter <>n electricity with the calm statement ' electricity is a fluid,' and then proceed to tell about Dr. Franklin's experiments with the kite. Thin had much more ' cocksurenees ' about it, and left the youthful mind in a much more satisfied condition than the vast amount of information as to what electricity will do and the explanations which do not explain which appear in the modern school books. Even ordinary everyday milk has its mysteries. It has been found that by patting milk into hollow steel cylinders and applying great hydraulic pressure it can be kept sweet for days. A pressure of seven tons to the t-quare inch for an hour has been found to delay fermentation or ' souring ' of the milk for seven days, while samples kept under pressure of fifteen tons to the square inch were sweet and fresh at the end of a fortnight. Here is something- else to think over. How does mere pressure prevent fermentation 1