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A paper was read entitled <c Notes on the Origin of several 
Mechanical Inventions, and their subsequent application to 
different purposes.” Part II. By J. C. Dyer, V.P. 
The Employment of Steel for . Transferring Engravings . 
At the beginning of this century, upon the death of 
Washington, medals to commemorate that event being called 
for, Mr. Jacob Perkins (then a silversmith at Newbury Port, 
near Boston) undertook to supply them, and, as they were 
required in large numbers speedily, he devised a summary 
process of transferring the engraved design, from prepared 
steel dies or stamps, by which he obtained several from one 
original die, and thus a vast number of medals were 
rapidly produced. Shortly after Mr. Perkins applied the 
same principle of transferring engravings for bank notes, on 
which very elaborate designs were printed to prevent or 
render their being forged very difficult by the hand of the 
engraver. To effect this he procured cast steel plates, and 
decarbonated their surfaces to the depth of about one- 
sixteenth of an inch, which were thus converted into very 
soft and pure iron ; the letters and designs for the notes 
being then engraved upon them they were case hardened 
and tempered for use , but in lieu of printing from these 
plates they were used as dies for making others to print 
with. His next process was to prepare a cast steel cylinder, 
which in like manner was decarbonated at the surface, and 
then under a strong traversing pressure it was rolled over the 
letters and figures engraved on the hardened plate, and these 
engravings were taken up in relief on the surface of the soft 
cylinder. This cylinder being then hardened and tempered, 
was used to transfer, by means of the same traversing pressure, 
the entire work upon its surface, to any number of copper or 
soft steel plates for printing with. 
The adoption of this plan by several banks, for having very 
elaborate engravings on their notes, turned the counterfeiters 
