A Dead Reckoning Computer

Extract

The procedures of dead reckoning require a number of different steps, amongst which are distance measurement, angle measurement, construction of straight-line tracks, the solution of the vector triangle and the process of multiplication and division. The navigator's plotting and dead reckoning instruments are designed to meet these needs. The ruler serves both as a distance-measuring scale and as a means of drawing a straight line track; the protractor measures angles; the dividers measure distances and the Dalton computer serves both as a method of solving the vector triangle and as a circular slide rule for multiplication and division.