Figure 9. Height cf mean spring tides offshore along the Atlantic and Gulf of 

 Mexico coasts of the United States (Emery and Uchupi 1972). Contours are in 

 meters with extra contours for C.5 and 1.5 m. 



Figure 10. Relation of the tide range at Boston, Massachusetts, to the phases 

 of the moon over an annual cycle (Emery and Uchupi 1972). Upper envelope 

 encloses the daily tidal range v/ith levels of mean high tide, mean tide level, 

 and mean low tide shown. Lower portions show the relation of tides lower than 

 -30 cm (wide diagonal lines) with respect to the time of sunrise and sunset. 



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