SCIENCE SIFTINGS.

Auckland Star, Volume XXXVIII, Issue 250, 19 October 1907, Page 10

SCIENCE SIFTINGS.

A RIvEG OF MUD. The.-Vang-tse-Kiang,.the famous muddy river of China, .is. also one of the greatest, and its valley is the most densely populated and closely cultivated riverbasin on the globe. It crosses the whole empire in its three-thousand-mile course to the sea. The river has a.different name in almost every province, and continually pours a flood of diluted mud through half "its valley,. colouring the ocean for a distance of several miles from land. ... ANTS TENACITY TO LIFE. * Ants are really very long-lived, considering their minuteness. TWo queens were under observation., for ten. .years, and one of Sir John Lubbock's ant pets lived into her fifteenth year. ■ Ants are very tenacious of. life after severe injury. Following loss of the entire abdomen they sometimes live two weeks, and in one case a headless ant, carefully decapitated by aseptic surgery," lived for 41 days. A carpenter ant, after being submerged eight days in distilled -water, came to life -upon being dried, so that they are practically proof against drowning. They can live long periods without food-; in one case the fast lasted nearly nine months. WHERE HAT STRAW COMES. FROM. In Italy to raise straw employed in making hats-the wheat is sown as thickly as possible, in order that the growth of the plant may be impoverished, as weU as to produce a thin stalk having toward the end from the last knot the lightest and longest straw. The wheat blooms at the beginning of June, and is pulled up by the roots by hand when the grain is half developed. If allowed to remain in the ground a little longer time- the straw would become brittle. About five dozen uprooted branches, the size of the compass of two hands, are. firmly tied together into little sheaves and stowed away in barns. Then the straw is again spread out. to'catch the heavy summer, dews and to bleach in the sun. After additional bleaching the straw is put into small bundles and classified. Finally it is cut close above the first joint from the top and again tied up in small bundles containing, about sixty stalks each and delivered to women in almost every private dwelling of the lower classes. A FJSMARKABLE OIL PIPE LINE. The Southern Pacific Company has contracted for the construction of an oil pipe line which, according to the "Iron Age," has several novel - characteristics. - The pipe is for carrying a very heavy and viscuous oil from the Kern River (California) oilfields to the sea board, a distance of 285 miles. The oil being exceedingly thick, it was found necessary to devise a method for causing it to flow through the pipe. Experiments were made on small sizes "i pipe through which a mixture of oil arid, water was allowed to flow. By twisting the. pipe, a rotary motion was imparted to the fluid, and the water, being the heaviet of the two liquids, surrounded the oil, and thereby reduced the co-efficient of friction. Another experiment, to determine the necessary twist to give to the pipe, was made by placing the mixture in a glass bottle, which .was... then put into a lathe. By revolving' it the ririm-" mum speed at which the water complete l ly encompassed the oil was found. The pipe-line as constructed.is.Bin diameter, and it has six spiral indentations 0.125ih deep. The first section of 31 miles has been in operation for several monthsj and the complete length will require 23 pumping stations located along the line. The estimated capacity of the. pipe is 23,000 barrels of heavy oil in 24 hours. THE AGE OF NIAGARA. In a recent paper, Dr. J. W. Spencer has given Some interesting data in respect of the "Age of the Niagara Falls." He has been engaged in investigations: for a monograph on the Falls, to be published by the Geological Survey of Canada. Soundings at all the points of great changes in the Gorge have been successfully undertaken,, borings were put down for the exploration of buried -valleys, and instrumental surveys made of the -original river-banks and the. physics of the stream. The mean recession of the crest-line of the Falls is found to be 4.2 feet a year under existing conditions, and this rate has approximately obtained for 227 years. But this' rate will not give the age of the Falls, on account of fewer great variations in the volume of the river and the height of the Falls themselves. The chief change in volume of water depends on the fact: that originally Lake Erie alone was discharged over the Falls, when the supply of water was only one-fifteenth of * thei present discharge. Above Foster's Flat the sudden -widening indicates the inflow of the other lakes into Erie, greater, water discharge, and greatly increased rapidity of recession. The Whirlpool is; on the site where the recession broke down the partition separating, the head of the Whirlpool-St. David's buried gorge, and began to empty out "the contents of this vaUey. The cutting -with the full power of the water of the four lakes varied at times according to the i height of the fall, and is calculated to have occupied 3500 years. Thus the enI tire age of the Falls is given at 39,000 years.—"Knowledge." MARS. Telegrams received from the Lowell expedition to. the Andes announce that on July 2 Mr. Slipher photographed several of the canals, and that, on July 6 canals were seen double and oases were photographed. In the "Astrophysical. Journal" Professor Newcomb discusses the optical and psychoTbgicar principles involved ia the interpretation of the so-called canals of Mars. From the optical point of view hfe shows that" in the best refracting telescopes the effects of aberration, diffraction, and. atmospheric softening will materially increase the breadth of any linear marking. As a rough estimate he submits that a perfectly black line on Mars three miles in breadth might be visible if the surface of the planet were perfectly. uniform, but, as it is not, the actual breadth would have to be increased to eight or ten miles in order that the feature might be differentiated from, those surrounding it. Aberration, etc., would spread a marking of this width for some twenty miles on each side, so that the apparent breadth in the telescope would be fifty miles or upward. Allowing this width to each of the 400 canals mapped by Lowell, the total area covered would be 33,000,000 square miles-, the actual surface of Mars extending over some 55,000,000 square miles. Although this large relative area does not disprove the objective -reality of. the. canal sys.teju, it shows how wide the interpretation of the results must of necessity be. when the whole network is crowded .on to a disc only 20Ln. in diameter... . .