Franklin Peale Peale designed a new machine to cut planchets, or blanks, from metal strips. This machine remained in use, almost unmodified, until 1902. Another of the steam-powered machines Peale had installed on his return was a milling machine, which was used to "upset" the coin—to form a rim around it. A Contamin portrait lathe was imported from France and installed at the Philadelphia Mint in 1837. Prior to this time, all coin dies for American coins had to be made individually, by hand at Philadelphia. Once the lathe was installed, they could be reproduced mechanically by the pantograph-like device. The first
Metal roof since they have approximately the same appearance and workability. Metal roof A metal roof is a roofing system made from metal pieces or tiles characterized by its high resistance, impermeability and longevity. It is a component of the building envelope. Zinc, copper and steel alloys are commonly used. Copper has played a significant role in architecture for thousands of years (see: copper in architecture). In the 3rd century B.C., copper roof shingles were installed atop the Lovamahapaya Temple in Sri Lanka. The Romans used copper as roof covering for the Pantheon in 27 B.C. Centuries later, copper and its alloys