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Show Keeping Up Wit&Science Peep-Foais Quakes Not So Destructive as Surface Types By OK. KKANK THONE Washington. Deep -focus earthquakes,, disturbances whose actual centers are scores or hundreds of miles underground, account for about ten per cent of all recorded re-corded shocks. They release tremendous amounts of energy, en-ergy, yet seldom cause the death and destruction for which the more numerous surface earthquakes are re-isponsible. re-isponsible. "N "A summary study of deep-focus earthquakes lias recently been made by Drs. Andrew Lcith, of the University of Wisconsin, and J. A. Sharpe, of the Los Angeles laboratory labora-tory of the Western Geophysical company. They are convinced that except for factors introduced by the great depths themselves, there is no essential diilerence between the deep and the shallow earthquakes. Two Great Earthquake Zones. Both types occur in the same gen-.jT3l gen-.jT3l regions of the earth one a great horseshoe-shaped zone roughly rough-ly arching about the Pacific, the other stretching in a long line from Portugal to Formosa. Both types vary greatly in amount of energy released. Due largely to their great depths, the deep class of earthquakes earth-quakes have surface results more widespread and diiTuse, hence less destructive, than the shallow-focus disturbances. Deep-focus earthquakes may occur oc-cur at all depths from 100 kilometers kilo-meters beneath the surface to 700 kilometers kil-ometers the greatest depth for any earthquake thus far on record. Where the vast stresses needed to power such earthquakes come from is still pretty much of a riddle. Cycles of deep earthquakes have been correlated with the forces resulting re-sulting from the moon's movements and other outside factors, but the stresses involved in these are so small that their action is undoubtedly undoubt-edly that of triggers rather than of main cause. Alaska Flowers Reveal Prehistoric Villages Washington. Flowers that bloom in Alaska can help explorers detect de-tect prehistoric American 'illages, - hidden underground. Importance of this botanic clue in re-discovering the past is stressed by Dr. Ales Hrdlicka of the Smithsonian Smith-sonian institution in a report to Science. Sci-ence. At the village trash heaps and ruins, the earth is mixed with animal ani-mal bones, shells, ashes, rotted wood, and organic refuse, and in this distinctly different soil spring up plants different from those dominant dom-inant in the neighborhood. At Aga-tu, Aga-tu, at the western end of the Aleutian Aleu-tian island chain. Dr. Hrdlicka found village sites covered with high stout grass on the slopes, and a thicket of wild parsnip, monkshood monks-hood and ether flowering plants """" fover the top. In locating hundreds of these sites far archeological exploration. Dr. Hrdlicka learned to detect an old village site, by its plant covering, as far away as he could see it clearly. Diver 420 Feet Down, Pressure 320 Tons Milwaukee. Max E. Nohl, diver, who descended to a depth of 420 feet in Lake Michigan recently, withstood with-stood a pressure on his body of 320 tons more at that depth than he did at the surface. Atmospheric pressure of 15 pounds to the square inch adds up to about twelve tons when all the 3,500 square inches of the average man's skin are considered. At 420 feet the pressure is about 197 pounds to the square inch. Dissolved gases in the human blood stream and body cells enable us to resist the pressure of the atmosphere. at-mosphere. At shallow depths, compressed com-pressed air helps a diver to resist re-sist water pressure, but as the pressure pres-sure increases, nitrogen from the air dissolves in the blood stream, causing trouble if the diver comes to the surface too rapidly. "Bends," or caisson disease, a common and serious illness of divers, div-ers, is caused by collecting nitrogen nitro-gen bubbles in the capillaries. These bubbles act as blood clots. Leadleaf for Paints Cambridge, Mass. Lead, long used in paint in the form of its oxides, ox-ides, is now coming into use as the main ingredient of a protective paint that is somewhat like familiar aluminum paint. The lead is in the form of foil broken up into fine individual in-dividual flakes and the vehicle em-.ployed em-.ployed is tung oil or some synthetic resin. Early Man's Relies Found in Hrittany by Two Scientists Paris. Traces of earl man's existence have turned up in n new part of the world Brittany, that upper left-hand left-hand corner of France that is washed by the English channel chan-nel on the north and the Atlantic At-lantic ocean on the west. K idonoe that prehistoric human beings lived or visited in this region, re-gion, in the days when crude stone tools were man's most typical han-: diwork. is beginning to come to light. I The first discovery, made recently, recent-ly, consisted of such tools, some abovit 30.000 years old, others perhaps per-haps 60.000. These blasted the theory that human hu-man beings never reached this part of Europe in their wanderings until un-til the New Stone age, a mere 8,000 i years ago. Now two French archeologists, M. and Mnie. St. Just Pequart. have searched small islands otT the i Brittany coast, where prehistoric j man's relics, if any, would escape : the destruction wrought by farm-! ing and other activities of civilian-, tion. ! Camping Ground Found. On one barren islet called Teviec they have found what they wanted. It is a camping ground where pre- i historic men lived, and buried their j dead. These people were not so ancient as the ones whose stone tools were found on the Brittany mainland. They lived in the Meso- j lithic, or Middle Stone, age, sand- j wiched between the Old Stone age j and the New, making them perhaps j 15. COO years old. j The French archeologists found quantities of the kitchen refuse of these Middle Stone age people, in- . eluding the bones of animals they ate, shells, fragments of broken pot- tery dishes. Their flint implements j have also come to light. They left no trace of houses, and probably . lived in tents. Subsea Canyons Clue Found in Great Lakes L'rbana, 111. Ice-carved lake basins ba-sins in North America and Europe may supply clues that will solve j the problem of the subsea canyons ! which have excited the interest of ! geologists recently. In reviewing 1 the evidence of ice-cutting of the i basins of the Great Lakes and other i lake basins. Dr. Francis P. Shep- ! ard. University of Illinois geologist, I points out that an average thick- j ness of the continental ice of four ; miles or more during the most re- j cent glacial period would account for both the cutting of the deep ; lake basins in the northern parts of Europe and America and a lower- ; ing of sea level sufficient to ac- j count for the submerged canyons. ' Supporting the theory that the ba- 1 sins of the Great Lakes were largely large-ly cut out by glacial ice, Dr. Shep- ard cites the evidence of large j amounts of fresh rock piled on the j southern shores of the lakes. The . ice came from the north, and the rock almost certainly came from somewhere in the present lake ba- j sins. Fuzzless Peach Developed After Years of Research Blacksburg, Va. Peaches with smooth, waxy skins like plums, quite free from the fuzz which many persons find objectionable, can now be grown, as a result of a quarter of a century of patient breeding work by Dr. Fred W. Hofmann, research horticulturist of the Virginia agricultural agri-cultural experiment station here. Dr. Hofmann crossed plum-peach with Elberta, and then crossed the hybrid offspring with the J. H. Hale peach, believed to be a seedling variety va-riety of Elberta. Further breeding breed-ing produced, finally, the peach Dr. Hofmann was looking for: waxy-skinned, waxy-skinned, fuzzless, good-sized, round and evenly shaped. Tne flesh is yellowish-cream colored, changing j to reddish around the pit, stone free j and small, flavor and texture superior. supe-rior. The skin color is reddish orange yellow, with a wash of attractive at-tractive dark carmine. Don't Talk So Loud When Speaking to the Deaf Iowa City, Iowa. Deaf people do not enjoy loud talk. When allowed to adjust the loudness loud-ness of the voice to which they are listening, individuals with normal ears prefer to have it 33 decibels, or loudness units, above the level at which it is audible. Hard-of-hearing persons will adjust the same speech at a loudness only 23 to 20 decibles above their threshold of hearing. This was discovered in experiments ex-periments at the University of Iowa by Dr. Noble H. Kelley. Deaf ears function differently from normal ears, Dr. Kelley found. In speaking to those with normal hearing you will have most difficulty in making your consonant sounds understood; vowel sounds are most intelligible. For the deafened, the consonants are recognized practically practical-ly as easily as the vowels. |