NOTE.—Contains on reverse, Dates on which navigation was possible and on which navigation opened at ports on Great Lakes during last 5 years.—Highest velocity of wind, direction from which coming, and date of occurrence during Apr. 1900-11.— Distribution of wireless telegraph stations on Great Lakes, and call fetters for each.— Total amount of snow in inches, umnelted during Apr. 1900-11.-Approximate location of submarine signal bell stations, Mar. 1911.
The meteorological charts of the north Atlantic, north Pacific, and Indian oceans, and the Great Lakes, monthly, and of the south Atlantic and south Pacific oceans, quarterly, are issued by the weather Bureau for gratuitous distribution to cooperating shipmasters and others interested in ocean meteorology.