3. They draw these plates between rollers to bring them to an even thickness all along and every plate of the same thickness, and it is very strange how the drawing it twice easily between the rollers will make it as hot as fire, yet cannot touch it.
4. They bring it to another pair of rollers, which they call adjusting it, which bring it to a greater exactness in its thickness than the first could be.
5. They cut them into round pieces, which they do with the greatest ease, speed, and exactness in the world.
6. They weigh these, and where they find any to be too heavy they file them, which they call sizeing them; or light, they lay them by, which is very seldom, but they are of a most exact weight, but however, in the melting, all parts by some accident not being close alike, now and then a difference will be, and, this filing being done, there shall not be any imaginable difference almost between the weight of forty of these against another forty chosen by chance out of all their heaps.
7. These round pieces having been cut out of the plates, which in passing the rollers are bent, they are sometimes a little crooked or swelling out or sinking in, and therefore they have a way of clapping 100 or 2 together into an engine, which with a screw presses them so hard that they come out as flat as is possible.
8. They blanch them.
9. They mark the letters on the edges, which is kept as the great secret by Blondeau, who was not in the way, and so I did not speak with him to-day.
[Professor W. C. Roberts-Austen, C.B., F.R.S., chemist to the Royal Mint, refers to Pepys's Diary and to Blondeau's machine in his Cantor Lectures on "Alloys used for Coinage," printed in the "journal of the Society of Arts" (vol. xxxii.). He writes, "The hammer was still retained for coining in the Mint in the Tower of London, but the question of the adoption of the screw-press by the Moneyers appears to have been revived in 1649, when the Council of State had it represented to them that the coins of the Government might be more perfectly and beautifully done, and made equal to any coins in Europe. It was proposed to send to France for Peter Blondeau, who had invented and improved a machine and method for making all coins 'with the most beautiful polish and equality on the edge, or with any proper inscription or graining.' He came on the 3rd of September, and although a Committee of the Mint reported in favour of his method of coining, the Company of Moneyers, who appear to have boasted of the success of their predecessors in opposing the introduction of the mill and screw-press in Queen Elizabeth's reign, prevented the introduction of the machinery, and consequently he did not produce pattern pieces until 1653 . . . . It is certain that Blondeau did not invent, but only improved the method of coining by the screw-press, and I believe his improvements related chiefly to a method for 'rounding the pieces before they are sized, and in making the edges of the moneys with letters and graining,' which he undertook to reveal to the king. Special stress is laid on the engines wherewith the rims were marked, 'which might be kept secret among few men.' I cannot find that there is any record in the Paris mint of Blondeau's employment there, and the only reference to his invention in the Mint records of this country refers to the 'collars,' or perforated discs of metal surrounding the 'blank' while it was struck into a coin. There is, however, in the British Museum a MS. believed to be in Blondeau's hand, in which he claims his process, 'as a new invention, to make a handsome coyne, than can be found in all the world besides, viz., that shall not only be stamped on both flat sides, but shall even be marked with letters on the thickness of the brim.' The letters were raised. The press Blondeau used was, I believe, the ordinary screw-press, and I suppose that the presses drawn in Akerman's well-known plate of the coining-room of the Mint in the Tower, published in 1803 ['Microcosm of London,' vol. ii., p. 202], if not actually the same machines, were similar to those erected in 1661-62 by Sir William Parkhurst and Sir Anthony St. Leger, wardens of the Mint, at a cost of L1400, Professor Roberts-Austen shows that Benvenuto Cellini used a similar press to that attributed to Blondeau, and he gives an illustration of this in his lecture (p. 810). In a letter to the editor the professor writes: "Pepys's account of the operations of coining, and especially of assaying gold and silver, is very interesting and singularly accurate considering that he could not have had technical knowledge of the subject.">[
10. They mill them, that is, put on the marks on both sides at once with great exactness and speed, and then the money is perfect. The mill is after this manner: one of the dyes, which has one side of the piece cut, is fastened to a thing fixed below, and the other dye (and they tell me a payre of dyes will last the marking of L10,000 before it be worn out, they and all other their tools being made of hardened steel, and the Dutchman who makes them is an admirable artist, and has so much by the pound for every pound that is coyned to find a constant supply of dyes) to an engine above, which is moveable by a screw, which is pulled by men; and then a piece being clapped by one sitting below between the two dyes, when they meet the impression is set, and then the man with his finger strikes off the piece and claps another in, and then the other men they pull again and that is marked, and then another and another with great speed. They say that this way is more charge to the King than the old way, but it is neater, freer from clipping or counterfeiting, the putting of the words upon the edges being not to be done (though counterfeited) without an engine of the charge and noise that no counterfeit will be at or venture upon, and it employs as many men as the old and speedier. They now coyne between L16 and L24,000 in a week. At dinner they did discourse very finely to us of the probability that there is a vast deal of money hid in the land, from this:—that in King Charles's time there was near ten millions of money coyned, besides what was then in being of King James's and Queene Elizabeth's, of which there is a good deal at this day in being. Next, that there was but L750,000 coyned of the Harp and Crosse money,
[The Commonwealth coins (stamped with the cross and harp, and the inscription, "The Commonwealth of England") were called in by proclamation, September, 1660, and when brought to the Mint an equal amount of lawful money was allowed for them, weight for weight, deducting only for the coinage (Ruding's "Annals of the Coinage," 18 19, vol. iii., p. 293). The harp was taken out of the naval flags in May, 1660.]