A New set of logarithmic solar tables, [electronic resource] : Calculated and constructed for determining the latitude at sea, by taking two altitudes either in the forenoon or afternoon, with the intermediate time, by a common watch; and that with ease and accuracy, independent of the sun's meridional altitude. This most excellent and useful performance, doth not only produce the true latitude at any time between nine o'clock in the morning, and three in the afternoon; but also gives the true time of the day, when the greatest altitude was taken, to twenty seconds by the tables; and if a greater degree of accuracy is required, the same may be done by taking proportional parts. Whence the sun's azimuth may be determiend by one single proportion. To which is added, a complete theory, illustrating the rationale of this most useful discovery.