Apparatus for predicting the exact time of currents in terms of the year, month, day and hour

摘要

Apparatus for presenting tidetable data in a form visually readable to the average person in terms of the year, month, day and hour of occurrence, exacting information regarding current flow, i.e. the direction of current flow, the relative strength of current flow, and the period of current flow, at a given location. A preferred apparatus is comprised of a stator, and slide. The stator is suitably an elongate member along a horizontal side of which days of the week are scribed and scaled off in consecutive order, preferably with each daily period being further sub-divided into a morning period and evening period. The morning and evening periods are in turn sub-divided into hourly periods. A vertical scale provided on the stator ranges from a base line of zero upwardly, or in a positive direction, to a high point representative of the tidal range, and downwardly below the base line of 0, or in a negative direction, to a low point representative of the tidal range. The tidal range, suitably in feet, is representative of the rise and fall of the surface of the water, at the given geographic location. The slide, which is carried by the stator, is scribed with a generally sinuous wave form representative of the tidal range, suitably in feet, at a given location for each consecutive daily period over the range of data of a given period. The amplitude of the sinuous wave form is read from the vertical scale of the stator, for a given week day, or hourly period, as scribed upon the horizontal scale of the stator. From the lunisolar information given in this manner one can readily predict and observe, for the location, the precise hourly periods of current flow on any given day of the year, and their strength, direction and duration.