176 ANNUAL REPORTS OF DEPARTMENT OF AGRICULTURE. 



The North Athuitic charts contain on their face the normals of 

 pressure and tenij)cratiire; tables for re(hicin<; barometer obsf^rva- 

 tions for comparison with data on the charts; wind roses, with per- 

 centa^jes of jjales and cahna for each 5-defjree square of latitude and 

 lon<];itude; storm tracks of recent years; foi; areas and percentat^jes of 

 days with foi;; trade-wind limits; sailinj^ routes; ma<^netic-variation 

 lines; location of wireless-telegraph stations; tables of equator cross- 

 ings; a statement of the average conditions of wind and weather; 

 storm-warning signals of the United States, Canada, Mexico, Great 

 Britain, Ireland, Germany, ITolJand, France, and Portugal; and the 

 United States submarine distinguishing and warning flags. On the 

 reverse side appear as regular features articles on the temperatures of 

 the air and the water surface, and charts of the currents of the North 

 Atlantic and North Pacific Oceans. Special articles have been printed 

 on West Indian Hurricanes, Waterspouts, Cyclones and Anticyclones, 

 Weather Lore of the Sea, Fog and Fog Signals, and Ocean Currents. 



The South Atlantic charts contain much the same general informa- 

 tion as that appearing on the charts for the North Atlantic Ocean, 

 slight modifications, such as the omission of fog areas and the addition 

 of storm-warning signals for ports on the Indian coast, being the 

 chief differing features. The same general similarity and minor dif- 

 ferences are found in the charts for the North Pacific, South Pacific, 

 and Indian Oceans. 



The fog areas and the percentage of days with fog, as now shown 

 on the charts for tlie North Pacific and Indian Oceans and the Great 

 Lakes, have been pronounced particularly valuable features by those 

 using the charts. Mr. H. C. Thomson, engineer in charge of the sur- 

 vey for a short-hne railway and steamship route to Europe, states 

 that the fog data for the North Atlantic chart as revised by tne bureau 

 have been an invaluable aid to his project. He has interested himself 

 in an endeavor to secure fog data from Canadian lighthouses for 

 incorporation in an article to be published on fog of the North Atlantic 

 Ocean. The English Meteorological Office, on its chart of the North 

 Atlantic, continues to make use of the fog data and shading pub- 

 fished by the Weather Bureau. 



A chart has been prepared, and will be published at an earl}^ date, 

 showing the average direction and rate of movement of storm centers 

 in each 2^-degree square of latitude and longitude in West Indian 

 and Gulf waters. 



The charts for the Great Lakes were begun with the January num- 

 ber of this year. They contain on their face normals of pressure and 

 temperature; barometer reduction tables; wind roses; storm tracks; 

 fog areas and percentages of days with fog; arrows showing direction 

 of lake currents; magnetic variation lines; location of wireless-tele- 

 graph stations; a statement of the average conditions of wind and 

 weather; percentages of days with rain, snow, fog, gales, and calms 

 at lake stations; dates of opening and closing of ports on account of 

 ice; wind-barometer indications for the Great Lakes; storm-warning 

 signals of the United States, Great Britain, Ireland, and Canada; a 

 table of verifying wind velocities at Weather Bureau stations; and 

 the United States submarine distinguishing and warning flags. The 

 reverse side presents monthly tables of wind velocities; seasonal 

 tables of snow and ice; lists of lake wireless-telegraph stations, with 



