Science Siftings

New Zealand Tablet, 17 September 1908, Page 35

Science Siftings

BY « VOLT

. Highest Lake in the World.- . ' - On the"summit of the. Sierra Nevada Mountains is a lake known to tourists as Lake Tahoe. It is the 1 highest body of fresh water in considerable volume known to this or any country, for the recent Geodetic Survey reports its level as being nearly Booo.feet above that of the sea. Its temperature -never .rises higher than 40 degrees Fahrenheit, and it runs off into the Truckee river, which discharges itself into the lakes_^ of the Nevada that have no outlet, but whose waters are drunk up by the thirsty alkali soils of the Great American Desert. The lake never freezes. When people are drowned in its. waters .their bodies are never recovered. • In. the of the State there is not a single instance of recovery. There is no accurate survey of the lake, norjias there ever been made a careful analysis- of its water, such as would determine their specific gravity, but the fact remains that whosoever falls into them is irretrievably lost. The theory is that the lake itself is the crater of an extinct volcano, in size greater than any now extant ; that it is fed and. chiefly drained by subaqueous chan-' nels that carry into that whatever comes into it, and that its swirling currents thus, dispose of its flotsam: A Priest Inventor; A new and improved system of ore concentration Jy .. RevR cv- P., Brophy, of Omaha, -Neb., for which a United States patent had been granted- and which the - inventor believes will, by reason of its simple efficiency make a stir in the mining world, will soon make a practical appearance in the mining regions of the west In speaking of the matter in an interview with a newspaper reporter, Father Brophy said :— While engaged for many years in ministerial work on the frontier duty frequently called me to several of the mining camps in the mountains. My relations with prospectors, miners, and millmen were such that I soon became -acquainted with the mining situation, its wants and advantages. The question then, as now, how to separate the 'chaff from the wheat,' how to treat at a profit the refractory and low grade ores in which the whole Rocky. Mountain range abound, engaged the attention of all. It was plain that without some new and improved system of concentration the treatment or nigh-grade ores only was within the range of profit The same is the condition to-day, though the solution ° j the .P roblem has engaged the attention of mining and millmen the world over. ~ - The Barometer. That the barometer should be so important a tactor in indicating meteorological conditions is to many an unsolvable mystery. There should, however, be no difficulty in understanding that the simple principle underlying the construction is that the free and unfettered air balances a column of mercury, varying in height, according to the circumstances of the moment, whose average elevation at the level of the sea is thirty inches. It is known, because directly ascertainable, that thirty cubic- inches of mercury weigh close upon fifteen pounds avoirdupois, and therefore, as commonly expressed, the pressure of the atmosphere is, under normal- conditions, fifteen pounds on every square inch— equivalent to nearly- a ton on a square foot, more than eight and a half tons on a square yard, and of 100 tons on a square of ten and a quarter feet side. . Scientific calculations also place the aggregate weight of the atmospheric envelope surrounding the world at aW .5,000,600,000,000 of tons, and this iriay be represented as the weight of a solid leaden ball haying a diameter of sixty miles. Such figufes are really beyond human comprehension.