Great advances have been made in'the proc esses involved in coining as conducted in mod ern times. The substitution of the coining press operated by power for the hand screw press of olden times practically revolutionized the busi ness. The introdoction of automatic weighing machines for separating the blanks into "heavies," "lights," "standard" and "con demned," has simplified the process of adjust ing. In fact the silver coins, with the exception of dimes, are now separated by the automatic weighing machines. The very great improve ment in rolls for producing the coin strips from the ingot has made this new and rapid mode of selection possible. The draw-bench, made necessary to cure the defects of the rolls, has practically disappeared. Constant trying has produced rolls of such precision that the thick ness of a coin strip can be regulated to the thousandths if required.
The automatic selecting machine in use at the mint of the United States at Philadelphia was invented and constructed by Seycsse, an Austrian, at Vienna. The blanks are fed into the machine through a vertical tube the size of the diameter of the blank. The feed is auto matic and the pieces are conveyed into minute balances finely adjusted to grains, and by a com plex and ingenious arrangement of parts are, according to weight, whether light, heavy, standard or condemned lights, shunted into the conduits strictly according to their varying weights, and through these conduits, or ways, are delivered, each to its proper receptacle at the discharged end of the machine. The stand
ard and the accepted light pieces are then ready for milling. The heavy pieces are ad justed by weighing on a delicate balance, and if found to exceed the legal tolerance are reduced by filing the edge of the piece. By this method the necessity for hand adjusting is minimized and the rapid production of coin greatly facili tated. Other automatic selecting machines are employed in the mints of foreign countries, but have not been found so satisfactory as the Aus trian machine in this country.
One of the most difficult of the processes of coining has been the annealing process, be cause it is vital to the successful reduction of the ingot to the coin strip. Formerly the process was conducted in a furnace heated by wood fires. Much depended upon the fuel. Per fectly seasoned hard wood, preferably oak, was required for good work. In annealing gold strips in a wood furnace the strips were en closed in copper canisters, sealed to air tight ness, and remained in the furnace about three fourths of an hour. Silver strips were some times subjected to the heat for an hour or more.