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i 2 TABLE f —DAILY TIDE PREEDIC T IONS I ptelation of tide to cup rent—ill using these tables of tide predictions h mt,st be borne 3r• mind thUt they give the times and heights of h,t,h and low waters and i of the times of turning at the current or slocf water For stat;ons on tie cU`Ar coy sf there .s usually but 1-the differer ce betwae n the time of huh or low water and the begirning of ,b or Tod current, but for plat-s in narrow channels, Landlocked h& hors, or on tidal wers, the time of slack water may differ by several hours from the time of high or low water ,tared I The relation of the tisr,es of anti ,ow water to the turning of the current depends upon a number of factors, so no ssinole or general rule r=ip be given For the predicted tirro of slack water a,id o,her current data reference should be made to the tidal current table,, published by the National Ocean Service in n) ' separate volumes, one fo, the P,flanlic coast of North America and the other for the Pacific coast of :forth Amer ca and Asia Typical tide curves —The variations in the tide from day to day and Irom place to place are illustratr-d on the opposite page by the tide curves !or representative ports along the Pac,fic coast of the United States It will be noted that one of 'one chief characteristics of rhe tide in this region is diu nal inequality, i e , the difference in heig"its successive oign %raters or tow waters The largest inequality is in the low waters i although at Seattle there is also conssderabl, difference between the t%%o hsgn waters on certain days The importance of this inequality at Seattle is brought out by V , curve which shows that at times the two high waters of a day differ ay over 4 feet and the two iow waters differ by more than 8 feet At Ketchikan and Anchorage the inequably is 1-;s pronounced because Of Lhe large range of tide In These local bus the i principal variations in the tsoe -.ow the changes in the Moon s phase and distance rhe tide at Anchorage Is one of the largest in the wo id At Unalaska and Jt-tch Hai bor the „n of tide is such that it is semidsurnal around the times the Moon i,- on the Equator, but becomes diurnal arouno the times of mo>imun north or isouth declination of the Moor i i I 1 1 I 1 1