Walter Breen
While Wailes does not mention the denomination being struck, it must have been either silver or gold as he mentions edge milling (some gold denomination is most likely as this is mentioned later in the account). The edge devices, of course, were not formed by the feedfingers (nippers) as Wailes records.
The cent press was operated a bit differently according to George Escol Sellers. (Taxay, p. 98.)
In the rear room, facing on the alley, with a large lowdown window opening into it, a fly press stood, that is a screw-coining press mostly used for striking the old copper cents. Through this window the passerby in going up and down the alley could readily see the bare-armed vigorous men swinging the heavy endweighted balanced lever that drove the screw with sufficient force so that by the momentum of the weighted ends this quick-threaded screw had the power to impress the blank and thus coin each piece. They could see the rebound or recoil of these end weights as they struck a heavy wooden spring beam, driving the lever back to the man that worked it; they could hear the clanking of the chain that checked it at the right point to prevent its striking the man... The cent press appears to have been fed by hand at least until April 1799 as shown in a letter from Mint Director Elias Boudinot to Matthew Boulton: (Record Group 104, entry 3-Letters sent, Elias Boudinot to Matthew Boulton, April 22, 1799.)
... excepting that as to small Coin & Cents, the press is fed by means of a hopper, instead of being put under by hand.
By Sellers' early childhood (c. 1814) the press had been retrofitted with feedfingers as shown by his description of the press being operated by one man and his recounting of the striking of a cent: (Taxay, p. 98.)
One day in the charge of my elder brother I stood on tiptoe with my nose resting on the iron bar placed across the open window of the coining room to keep out intruders, watching the men swing the levers of the fly press; it must have been about noon, for Mr. Eckfeldt came into the room, watch in hand, and gave the signal to the men who stopped work. Seeing me peering over the bar, he took me by the arms and lifted me over it. Setting me down by the coining press he asked me if I did not want to make a cent, at the same time stopping the men who had put on their jackets to leave the room. He put a blank planchet into my hand, showed me how to drop it in, and where to place my hand to catch it as it came out...
Coining by screw press came to an end in 1836 with the introduction of the new steam-powered presses, and the cent, the first coin struck at the Mint, also became the first coin struck on the new press. (See the Mint Report for 1836-in the report Mint Director Patterson states: "On the 23rd of March last, the first steam coinage in America was executed at this Mint ... Since that time, all copper coins have been struck by this press ...")