_Tide Tables._--Can you, or any of your subscribers, give me a rule for
ascertaining the heights of tides and times of high water, the
establishment of the port, and rise of springs and neaps, being known? One
divested of algebraic formulæ would be preferred: say--
Establishment 10 h. 58 m.
Springs' rise 8½ feet.
Neaps' " 2 feet.