| United States. Department of Commerce - 1952 - 508 páginas
...have full knowledge of the eas around it, the extent of fishing grounds and other submerged lands, he rise and fall of the tide, the direction and strength of sea currents, he variation of the compass, and a knowledge of magnetic disturbances hat affect communications. As... | |
| United States. Congress. Senate. Committee on Appropriations - 1956 - 1318 páginas
...our country must have full knowledge of the seas around it, the extent of fishing grounds and other submerged lands, the rise and fall of the tide, the direction and strength of sea currents, the variation of the compass, and a knowledge of magnetic distrubances that affect communications.... | |
| United States. Congress. Senate. Committee on Appropriations - 1956 - 734 páginas
...our country must have full knowledge of the seas around it, the extent of fishing grounds and other submerged lands, the rise and fall of the tide, the direction and strength of sea currents, the variation of the compass, and a knowledge of magnetic distrubances that affect communications.... | |
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