It will be remembered from what has been above stated, that a reward of 10,000L.

was to be given to the person who should contrive a method of determining the longitude within one degree of a great circle, or 60 geographical miles; 15,000L.

within 40 geographical miles; and 20,000L.

within 30 geographical miles.
It will, in these days, be scarcely believed that little more than a hundred and fifty years ago a prize of not less than ten thousand pounds should have been offered for a method of determining the longitude within sixty miles, and that double the amount should have been offered for a method of determining it within thirty miles! The amount of these rewards is sufficient proof of the fearful necessity for improvement which then existed in the methods of navigation.

And yet, from the date of the passing of the Act in 1714 until the year 1736, when Harrison finished his first timepiece, nothing had been done towards ascertaining the longitude more accurately, even within the wide limits specified by the Act of Parliament.