The sea-man's practice containing a fundamental problem in navigation : experimentally verified namely touching the compass of the Earth and sea, and the quantity of a degree in our English measures. Also, an exact method or form of keeping a reckoning or journal at sea in any kind or manner of sailing. With certain tables and other rules used in navigation. As also the plotting and surveying of places: the latitude of the principal places in England: the finding of the currents at sea, and what allowances is to be given in respect of them /