Across
- 1. a type of sea chart common in Middle Ages that was used for navigation at sea.
- 5. the estimation of a ship's position from the distance according to the ship's log and the course steered by the compass, with corrections for currents and other factors, but without astronomical observations.
- 6. an instrument having a magnetic needle to indicate magnetic north.
- 7. the techniques used to obtain reliable measurements from photographs.
- 8. a portable timekeeper with a special mechanism for ensuring and adjusting its accuracy, for use in determining longitude at sea.
- 9. the techniques used to make measurements in space to determine the relative positions of map features.
- 10. from two Latin words meaning tablecloth and world, a graphic or verbal representation of the world as understood in the Middle Ages in Europe.
- 11. a method of surveying in which the stations are points on the ground at the vertices of a chain or network of triangles. The angles of the triangles are measured instrumentally, and the sides are derived by computation from selected sides or bases, the lengths of which are obtained by direct measurement on the ground or by computation from other triangles.
- 12. a device for plotting survey data directly from field observation. Consists of a drawing board on a tripod with a sighting instrument to measure and plot angles.
- 14. mean solar time of the meridian of Greenwich, England, used by most navigators and adopted as the basis of standard time throughout the world.
- 15. angular distance measured in degrees, minutes, and seconds north and south to the geographic poles from the equator.
- 16. angular distance measured in degrees, minutes, and seconds 180 degrees east and west from the Prime Meridian, the imaginary north-south line through Greenwich, England.
Down
- 2. the process of detecting or monitoring the properties of an object without physically contacting the object.
- 3. a precise surveying instrument having telescopic sight for measuring horizontal and vertical angles.
- 4. any prominent object on land that can be used in determining a location or direction.
- 7. a projection or representation of the whole or part of a sphere on a plane.
- 13. an astronomical instrument for measuring angles, primarily altitudes of celestial bodies, to determine latitude.