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Show GREAT GLACIERS OF SAND MOVE ACROSS PLAINS, INUNDATING VEGETATION AND SHRUBBEKI . a .1 Ik. T hIUa .l.lrll J -f --A fnt.t. t U n Sand "glaciers" of the type that have taken possession of several hundred acres of fertile farm land near Hutchinson, Kan., are subjects sub-jects of Immense interest to geologists, geolo-gists, according to Prof. Thomas C. Chambcrlin, head of the department of geology at" tho University of Chicago. They arc especially interesting in-teresting in that they are rarqly encountered. The Kansas phenomenon consists con-sists of a moving mountain of sand. It was part of a range of sand hills and for years It kept Us place, behaving be-having with as much steadfast dig-. nity:as is common to sand hills. A year ago. however, it began to move. It continued to move month by month, until recently, when it was stopped by tho channel of the L.1UK Arkansas River, into which it had thrust Itself. Resident of the country 'for miles around" were puzzled by what seomed to them an r '-'f inexplicable freak of nature. "Tiro movement of the sand hill is not at all a mystery," sa'Id. Prof. Chambcrlin. "Occurrences, of the', kind, though not froquent. have been observed often enough, so that geologists understand pretty " well, their nature and 'cause. " 'Sand glacier.' as such a mass is - commonly called, Is a misnomer," continued tho professor. "While the slide has some characteristics of glaciers, it is much more properly related to landslides. "The causes are not difficult to trace. A river eating away under Its bftnk may be responsible for a small one. In this case, however, whoro tho movement Is on a larger scale, the cause Is slightly different. A very wet season or a series of wot seasons soaked through the sand until water reached the clay subsoil. This became slippery and on It tho great body of Eand began to slip. This is the usual way in which tho slides develop. "Progress of the slide varies in speed according to the 3lopo of the clay on which the sand rests and according lo the weight of the body which Is set In motion. It may bo very slow, as In this Kansas case, and unattended "by danger to thoso who reside In the vicinity; or, once under way. the motion may bo accelerated ac-celerated to such a rate that it is known as an avalanche. The sand glacier of Kansas and the avalanches ava-lanches Of the Alps and of tho Rocky Mountains are one and the same thing except In the rato of thoir motion. "Tho Culebra slides, which have been such a problem to Panama Canal engineers, are a perfect Illustration, Illus-tration, on a big scale, of the type to which tho Kansas phenomenon belongs. Here an Immense body of sand, rock and soft earth, which has been at rest, had its equilibrium upset by the excavations for the canal. With a part of its support gone the wholo body has been tumbling down, from time to time, into the ditch, and It will so continue con-tinue to fall until an equilibrium has again been reached. "In the same manner the Kansas sand hill has moved, though moro slowly, month after month, meeting no obstruction of slzo sufficient to '.ill it, until-It s'.r,!cl: tho rlvo.- bed. here it has been stopped and there ir will be halted permanently, for It Is not likely that hills there aro Isrge enough to fill and surmount the channel of a good sized river. "There are no practicable means of arresting by human offort thd movement of a whole hillside llko this. With smaller slides a successful success-ful effort can bo made to stop their progress, or at least guide them Into In-to paths where they will do a minimum min-imum of damage. In mining regions re-gions the first signs of a slide above the workings are mot by the erection of a wall or stockade. In the caso of a small bod of looso earth this will effectually halt the movement for good, or where the mass Is too great to be stopped it will bo shunted off to one side, away from the mine. "Small slides, too, may sometimes some-times be checked by means similar to those usod along the Baltic coasts to prevent the depredations of sand dunes. (Dunes aro unrelated unre-lated to these Kansas sand hills.) Here stockades aro constructed In squares, within which trees aro planted. The6e trees take root and anchor the loose earth above to the firm subsoil. "None Of these means could have been used for the Kansas trouble, however. That was a movement of too great slzo to be checked. Moreover, More-over, as I have said, the progress of that slldo Is probably at an end now that the bed of the river has been reached." An article by James Taft Hatfield Hat-field in which he describes the Immense sand dunes of Germany and their shifting nature, is recalled. re-called. Professor Hatfield told of his journey from the northeastern tip ol Germany, aftor crossing the Russian frontier, along tho coast of tho Baltic Bal-tic sea, through a country tho formation for-mation of which ho described as a "long, narrow barrier (nohrung) for 'if',:,; shifting dunes of sand, facing the sea and inclosing an extended basin of shallow water or 'haff.' " And again, speaking of the dunes at other points, tho professor told or their appalling activity beyond SchwarzorL There they are the highest in Europe, nearly 250 feet. i he asserted, "bleak and naked" and advancing from west to east, re- ' J lentlessly pushing the coast farther J Into the sea or making little Islands . of sand in the wator. J Because of the dunes. Professor j Hatfield explained, the villages of the vicinity llvo In the shadow of calamity and in tho knowledge that within recent times many villages havo been swept away by tho onward on-ward progress of tho all-enveloping -j sand. Professor Hatfield praised the work of the German government ! In arresting tho "blowing of sand" f I by an ingenious mothod, Involving tho planting of pine trees, each In a lump of clay. In small squares or divisions, staked off with plckots along tho length of these wandering wander-ing mountains of sand- i |