In 1875 Frenchman Marcq St. Hilaire improved upon Sumner's trigonometric calculations. These calculations were later used to supplement dead reckoning , a more precise method of correcting for drift using triangular calculations of velocity. Dead reckoning allows a navigator to plot where a craft will be at any time, making it possible to plan a journey in its entirety before the start of the journey. Matthew Fontaine Maury made famous studies of wind and weather and helped in the development of government aids to navigation. Today, electronic devices such as radar and loran are widely used in navigation.
Most vessels use an automatic pilot.
The digital computer , another tool, works so fast that it can provide continuous information. It also has a memory to store information for use when needed.