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Show EMPLOYS SIMPLE BUSINESS METHODS How the Weather Bureau Forecasts Storms, Frosts, and Floods. Many peoplo have an idea that there is something mysterious and occult about the work of tho Weather Bureau in forecasting tho coming of Btorms, frosts, and floods. Not a few think that the observers must necessarily get their data by reading tho planets, tho stars and tho moon. As a matter of fact, tho forccastor of tho bureau foretells tho coming of disturbances in n businessliko way, vcry similar to that in which a man who has ordered a shipment of goods would estimate tho date of its arrival. arriv-al. Supposo a business man had ordered order-ed a carload of pineapples from the Hawaiian Islands. Ho would know tho average timo it would tako tho steamer to make tho trip to the Pacific Pa-cific port, tho average timo for unloading unload-ing and loading into refrigerator cars, and tho averago number of days to bo allowed theso cars for their trip across tho continent to New York. His estimate, howover, would bo subject sub-ject to error, because tho steamship might l)e delayed by fog or tho cars mjght meet with an accident- Stpj:m8, like pineapples, as a rule dnot originate in tho United States. illOJpniTin to 11Q armn trnrr. U Tll.il i Anucomo to us, somo from tho Phil-i Phil-i iPPino. Jnpan slbern Alaska.Can-i Alaska.Can-i J' orthe Gulf of Mexico. The .Weather Bureau gets cablo, telegraphic, tele-graphic, or wireless notlco of a fore-ign fore-ign storm. Nation after station, or vessel aftor veiSel reports tho storm's arrival in its JwJghborhood, so that tho general direction and rate of progress pro-gress can bo dctetmined very early, in fact, tho arrival of somo can be foretold 10 days in advance. The forecasters watch for tho re-yjfir5-i2Wjarometer which is tho storm center aroun-wYiVVwthf. ..winflq blow. This whirl or eddy movesbodi-ly movesbodi-ly forward with tho general eastward drift of about 050 milos a day in our latitudes. Tho forecaster determines tho dircction,df movement of the storm and Uvclocity. JVhcn vathor disturbances aro ro-portedho ro-portedho forecasters know from ex-perj'rfco ex-perj'rfco about how long it takes them treach our Pacific const. nm . itoow long after they will reach the i Atlantic coast. For example, if n Btorm coming from Siberia drifts eastward around tho tho North Polo and reappears in Alaska, it should ap-pear ap-pear in Washington and Oregon in about two days; should got to the Great Lakes in six days and to the Atlantic coast in seven or eight days. Unexpected condition may delay storms or divert them from the straight track, just as a refrigerator IrZ b0'hrWn 0fr it3 schuo or be shipped by accident on a wrong road. Somo of these storms deplete themselves by running into regions of high barometer which aro of greater magnitude and extent than the storm I itself Some of them, however, travel completely around tho world. To keep tab on cold wayes that , como into tho United States from Canada and Alaska, the Weather Bureau studies tho Canadian Weather reports. England sonds reports from Iceland the British Islands, and Con! tinental Europe, and daily reports como from St. Petersburg on the con-JIUons con-JIUons in Russia and Siberia. The same business-like methods used in tracing tho track of a storm is applied in determining tho arrival of frosts. Flood forecasts aro macfo in much the same way. Information as to the amount of rainfall at tho head waters of streams that causo floods aro covered cov-ered by telegraphic reports sent by local observers. As this rain reaches I the main channel, tho height of the water in tho channel i3 determined by successive gauging stationB. Past records established how much a height say, of 20 feet at Dubuque, Iowa, will produce at Davenport, another station 80 miles down the Mississippi. This plan is followed all tho way down tho river, and at each point full allowance Jb made for tho effects of water from tributaries, and from additional and local rainfall. Ab a result of theso observations in tho recent flood tho people of Cairo had warning n week or 10 days in advance. Tho Pittsburg district can be given only 12 to 24 hours' notice, becauso a flood is upom them within 24 hours after a heavy rain storm. I |