Warden of the Mint

Newton became Warden of the Royal Mint in April 1696 at £500 a year, thanks to his patron, Charles Montague, the Chancellor of the Exchequer:

I am very glad that at last I can give you a good proof of my friendship, and the esteem the King has of your Merits. Mr Overton the Warden of the Mint is to be made one of the Comrs of the Customes and the King has promised Me to make Mr Newton Warden of the Mint, the Office is the most proper for you 'tis the Chief Officer in the Mint, 'tis worth five or six hundred pounds per An, and has not too much bus'nesse to require more attendance than you may spare.

Montague to Newton, 19 March 1695/6, Corres, IV, p195

At this time the Mint occupied the narrow street between the Inner and Outer Curtain walls of the Tower of London. Newton moved to London to take up the appointment and presumably first lived in the Warden's house inside the Tower walls. By November 1696 he had moved to a more pleasant house at 88 Jermyn Street.

The Letters Patent formally appointing Newton are dated 13th April 1696 and on 2nd May he took an oath not to reveal the ``new Invention of Rounding the money & making the edges of them with letters or grainings''. These processes of marking the coins' edges were introduced in 1662 to prevent the practise of clipping off some silver without detection. Round their circumference the 3mm thick English one pound coins still bear the words Decus et tutamen meaning An ornament and a safeguard.

Although the Mint had been producing coins with milled edges for thirty years, a large number of clipped and badly worn unmilled coins were still in circulation and legal tender. This was causing inflation and was a serious problem due to the expensive war with France in progress at the time. The government decided to recall all unmilled coins and recoin them with the new machines and Newton took part in the administration of this - although the Master of the Mint was responsible for overseeing matters directly relating to coin manufacture.

In 1700 Newton himself became Master of the Mint. Although originally a subordinate of the Warden, the Master had come to be the senior position. It was certainly the most lucretive, since Newton received a payment for every pound of silver coined - on average this amounted to £1000 a year in addition to his salary of £600.