National Geographic : 1897 Oct
UNITED STA TES DAILY A TMOSPHERIC SUR VEY 299 long in use, its observers were quick to detect and point out cer tain serious and hitherto unsuspected faults, necessitating con siderable corrections in nearly all accumulated data relating to that subject. Instruments were also improved and methods greatly changed, increasing at once the precision and rapidity of gravity measurements. Expeditions have been sent to various quarters of the globe for the purpose of gravity observations, and Coast Survey pendulums have swung in all continents except Australia, in most important cities, on several of the highest mountains, and on many islands in the several oceans. No others have been vibrated so near the pole as these and none over so wide a range in longitude. The results of these operations, together with the measurement of the great arc of unrivaled length, form a contribution of no ordinary interest to the more precise solution of the great problems of dimensional geography. UNITED STATES DAILY ATMOSPHERIC SURVEY* By Prof. WILLIs L. MOORE, Chief of the U. S . Weather Bureau The United States Weather Service has been in existence twenty-seven years. During the past twenty-five years the daily synoptic charts of the service have shown the most comprehen sive atmospheric survey ever presented to the forecaster or to the broad investigator of the fundamental principles of storms. The vast region now brought under the dominion of bi-daily synchronous observations embraces an area extending 2,000 miles north and south, 3,000 miles east and west, and so fortu nately located in the interest of the meteorologist as to cut an important arc from the circumpolar thoroughfare of storms of the northern hemisphere. The extreme points of observation are Edmonton, in the Canadian Province of Alberta, on the northwest; St Johns, on the northeast; Key West, on the south east, and San Diego, on the southwest; and arrangements are now complete for a cooperation with Mexico similar to that in operation with Canada, which will in a few months extend the area of observation southward over Mexico and Yucatan. It is a wonderful panoramic picture of atmospheric condi * Read before the Geographical Section of the British Association for the Advance ment of Science, Toronto, August 23, 1897.