This was a popular inquiry in the last century, owing to the reward of £20,000 offered by Parliament in 1714 for the discovery of a means of accurately ascertaining the longitude at sea. The father of Johnson's friend, Miss Williams, is said by Boswell to have made" many ingenious advances" in this direction; but the reward was finally gained by John Harrison.

From Act 1 Scene 2 of She Stoops To Conquer