A BACKGROUND TO THE NEWS

Dominion, Volume 30, Issue 191, 10 May 1937, Page 7

A BACKGROUND TO THE NEWS

German Airships It is announced that the disaster to the airship Hindenburg will not make any difference to Zeppelin buildingA new airship, nearing completion, will take the Hindenburg's place. This new airship, a sister-ship to the Hindenburg, is known as L.Z. 130. Most of the hull has already been covered with cotton material. The inner hull is being painted to resist the effect of the sun’s rays; the outer coat will be silver in colour. The cabins will con tain space for 70 passengers. There are four engine cabins. Between the cobalt blue lacquered ribs of the airship runs what is called an axial gangwav connected with hatchways with the lower gangway. The nose is being built on the floor of the hangar, and will soon be ready to tit into place. Then the main part of the construction work will be complete. Helium. In some quarters the cause of the Hindenburg disaster is ascribed to the fact that the airship was using hydrogen instead of helium. After hydrogen, helium is the lightest of all known substances. It is a colourless, odorless, and tasteless gas. It was for these reasons that Sir William Ramsay suggested its use for tilling balloons. It has the enormous advantage of being incombustible. The chief source of helium at. the present time is the natural gas lields in the south-west of the United States. The inflammable components of the natural gas are liquelied, and these leave impure helium in the gaseous state. It is purified by passing it over charcoal at the temperature of liquid air, which results in the absorption of all the gases except helium and hydrogen. Adsorption is the adhesion of the molecules of gases to the surface of a solid body. In 1908 helium was reduced to the liquid state, and its boiling-point was found to be about 268 degrees below zero Centigrade. Solid helium has also been prepared. Liquid helium mixed with oxygen !,■? sometimes supplied to deep-sea divers instead of air, as helium is less soluble than nitrogen in the blood. Helium was found in the sun before its existence on the earth was known. The discoverer was the French astronomer, Janssen; the discovery was made on August IS, IS6S. when he was making observations of the eclipse of the sun. The name helium was given by Dr. Frankland, after the Greek word for the sun. It was left to Sir William Ramsay in 1895 to advance the world’s knowledge of helium. Hydrogen.

Hydrogen is the lightest of all gases. It occurs in very minute quantities in the atmosphere, escapes from volcanoes mixed with other gases, and is produced by the decay of various organic bodies. Hydrogen gas is also given off by some oil wells. Hydrogen forms two-thirds by volume of all the water in the world, and one-ninth by weight. It is an important constituent of all animal and vegetable matter, of all acids and hydrocarbons, and is also found in many of the "carbon compounds like alcohol, sugar, starch, and ether. It is the hydrogen in coal that makes the fire burn, and it is the hydrogen in a balloon or an airship that makes it rise above the ground. The balloon rises not because of any action on its part, but because the heavier air presses round and under it and pushes it up, just as when a cork is released at the bottom of a basin of water it is at once pushed to the top by the heavier water pressing round and under it. By means of intense cold and pressure, hydrogen gas can be first liquefied and then solidified. It becomes a colourless liquid at minus 252 degrees Centigrade, and if allowed to evaporate rapidly it becomes a white wax-like solid at minus 259 degrees Centigrade. In other words, hydrogen boils at 252 degrees below zero Centigrade and freezes at 259 degrees below zero Centigrade. It is because of its power to combine with oxygen and form water that the gas was given the name hydrogen by the French chemist Lavoisier. The word means “water-producer.” On London Bridge.

An editorial, “So This is London." in “The Dominion” on Saturday, mentioned that “a record number of touring citizens of the Dominion [of New Zealand] will stand occasionally on London Bridge, gazing at the mighty dome of St. Paul’s mocking the dismal vision of Lord Macaulay.” The reference is to a passage in Macaulay’s essay reviewing Danke’s “History of the Popes.” “And she [the Roman Catholic Church] may still exist in undiminished vigour, when some traveller from New Zealand shall, in the midst of a vast solitude, take his stand on a broken arch of London Bridge to sketch the ruins of St. Paul’s,”

The thoughts contained in the quotation are not original. The picture of a traveller from a remote land visiting the ruins of London is found in Volnay’s “Ruins of Empire” (1791), and elsewhere as early as 1745. When Macaulay was only 19, Shelley had written, in his dedication of “Peter Bell the Third,” of a coming time when “the piers of Waterloo Bridge shall become the nuclei of islets of reeds and osiers, and cast the jagged shadows of their broken arches on the solitary stream.” Populating Australia. The Australian Commonwealth Treasurer, Mr. R. G. Casey, has drawn attention to the fact that Australia s population must be limited until the growth of scientific knowledge ami expenditure enable the country to be slowly developed. In the present state of knowledge, nearly one-third of Australia is “practically useless,” another third is suitable only for sparse pastoral cultivation. Over half the total area, mainly on account of its inadequate and unreliable rainfall, contains less than one-three-hundredth of the total population. According to experts it seems certain that the present regional distribution of population would still be the best, even if the population were double or treble its present size. Professor Griffith Taylor classifies 21 per cent, of Australia as “fair temperate farming country.” Excluding half of this as too rugged, and half the remainder as too poor in_ soil or too far from transport facilities, five per cent, remains. At present only one and a half per cent, is devoted to agriculture. . ... All things considered, experts suite that the greatest population Australia could carry in its present state of know ledge is between 10 and 15 millions.