The circle of the mechanical arts : containing practical treatises on the various manual arts, trades, and manufactures (1813)
Martin, Thomas · London : Printed for Richard Rees · leaf 525
PRINTING. 507 two of which are called tympans, and the remaining one are stuffed with wool or hair, and covered over with a frisket. a pelt prepared for the purpose. One skin generally The following figure will afford a very good idea of makes two proper sized balls. When the skin has been this… … The tympans are square, and are made of three slips with a clean sheet of stout paper, and patted with the hand until no moisture remains on the surface. The of very thin wood, and at the top a piece of iron, still thinner ; that called the outer tympan is fastened with balls, when they are…
Technology · Industrial arts
Internet Archive · Getty Research Institute · Public domain (published before 1931). Free to use for anything.
