Science Sittings

New Zealand Tablet, 28 August 1913, Page 47

Science Sittings

151 ‘ VOLT.’

Pressure of the Sea. Deep-sea animals, says Dr. A. E. Shipley, F.R.S., in the Edinburgh Review, live at a tremendous pressure. Every five fathoms we descend in the sea the pressure increases by one atmosphere, and at a depth of 3000 fathoms the pressure on each square inch of the body of an animal amounts to three tons, whereas at the surface t>f the waters it is about 15 pounds. So great is this pressure that unless special precautionsare taken the glass of the thermometers which measure the bottom temperatures is crushed to powder. . The Dead Sea. • ■ Many persons imagine that the Dead Sea is nothing but sea water of Extreme saltiness, but that is a mistake. The name was given to the great salt lake by a writer named Jerome" because nothing could live in its waters. Owing to the density of the water, fish cannot sink in it, and they could not live if they did, s as some of the salts are powerful antiseptics, which means that they are fatal to any form of life. There is about three per cent, of chloride of lime in the Dead Sea.' About half the salt in the Dead Sea is chloride of magnesium, whereas nearly all the salt in the ocean is just common table salt. 5 A Heavy Load. The Engineering News has this to say of a truck load, recently hauled by a motor truck over the streets of New York, probably the heaviest ever hauled in city streets: The hauling was done by a La France hydraulic transmission motor truck, and the load to be hauled consisted 7 of a door frame for the safety deposit vaults to be installed in the basement of the new Clearing House building. The total load to be moved was 45 tons, the weight of a modern locomotive. The load per wheel on the truck carrying the door frame was 17,250 pounds. The Street Department refused to permit the load to be hauled through Wall street on account of possible injury to pavement. It therefore proceeded to its destination by 1 way of Front street, to South Ferry and then up Whitehall street and Broadway. The truck was hauled up a per 'cent, grad© without difficulty, and to demonstrate its starting power was .stopped on this grade and started again. Important Inventions. One of the most important American, inventions to be granted a patent was the Colt revolver. The next great American invention to receive a patent was the Morse telegraph instrument. The patent was issued June 20, 1840. The patent issued to Charles Goodyear, June 15, 1844, acknowledged his invention of the process of vulcanisation of India rubber. The . basic patent of the pneumatic air brake .was issued to George W. Westinghouse, April 13, 1869. In granting to Elias Howe his patent the patent office accorded to him the distinction of inventing the sewing machine. The patent is dated September 10, 1846. The ‘four ; motion feed,’ invented by A. B. Wilson and patented by him December 19, 1854, brought the sewing machine into universal use. Elias Howe made more than £BOO,OOO out of this single idea. The next inventor to demand world-wide attention through the medium of the United States patent office was Alexander Graham . Bell with his telephone. There are scores of patents covering the various parts of the telephonic instruments in the name of Bell, but the basic patents are .. but two —one was issued March 7, 1876, and the other June 30, 1877. Quickly following upon the heels of Prof. Bell came Thomas Alva Edison. Edison’s patent to the phonograph was issued February 19, 1878. Two years later, on January ,28, 1880, he patented the incandescent light. ,