prize7-7, Exercise 2: A balanced account of longitude

Model answer (check the details):

Paragraph 1: Finding longitude at sea needed a way to compare local time with the time at a reference place. Two methods emerged in the eighteenth century. The lunar-distance method relied on astronomers, who produced accurate tables of the moon's position, and on navigators who learned to measure and calculate from them. The other method needed a clock that would keep good time on a moving, damp and changing ship.

Paragraph 2: John Harrison, a clockmaker, built a series of timekeepers culminating in a watch-sized instrument that passed trials in the 1760s, and his work is rightly celebrated. His success came alongside astronomical work by figures such as Nevil Maskelyne, and within a system of prizes and tests run by the Board of Longitude. Chronometers took time to become common because of their cost, and lunar distances were still used for decades. Longitude was solved by astronomy and clockmaking together, not by one person alone.

Note: check each name and date against a scholarly source before using this account.