Knight's American mechanical dictionary : a description of tools, instruments, machines, processes and engineering, history of inventions, general technological vocabulary ; and digest of mechanical appliances in science and the arts . is fed alonbetween each impression, suca as to enable the next impressionto be delivered in the proper succe,s,siou for the sense of thewriting. At the end of a line the papL^r is shifted upwardand bick to tae commencemeat of another liue. Foucault,though blind, was successful iu business and mechanical enter-prises, and was a zealous friend of his afflicted fel
Knight's American mechanical dictionary : a description of tools, instruments, machines, processes and engineering, history of inventions, general technological vocabulary ; and digest of mechanical appliances in science and the arts . is fed alonbetween each impression, suca as to enable the next impressionto be delivered in the proper succe,s,siou for the sense of thewriting. At the end of a line the papL^r is shifted upwardand bick to tae commencemeat of another liue. Foucault,though blind, was successful iu business and mechanical enter-prises, and was a zealous friend of his afflicted fellow-men Johnstons printing apparaliis fnr Ike blind (United Statespatent. February 19, imi) differs from the precedin. in themode of operating. The letu-rs .iie arranged on the ends ofcylindrical plungers moving vertically iu tubes arranged nearthe margin of a disk, which is capable of rotation on a verticalaxis. Eich plunger has a letter in relief for the fingers of theblind, and acts m correspondence with a similar letter whichis to be impressed on the paper. The blind person feels roundthe disk until he finds the right letter. He then presses theletter and revolves the disk till he hears a click, when a pressure Fig. 3946. 0. Prlntim: Fri. is brought upon the letter at the spot where the paper is pre-sented. Each letter is brought to the same opeuiug to give itsimpression, and the paper rei-eives two , as iu Fou-caults; one between each letter for the spacing, .and anotherat right angles to the former for the distance between lines See \\ KlTL\£. Prinfing-frame. (Photoijniphi/.) Also knownas a 2>iessi(ri;-_fnimc. A quadi-augulav shallow which sensitized paper is placed beneath a nega-tive and exposed to the direct rays of the sky or^uftlie sun. Large printing-lrameshave always a pane ot plate-glass in iroiit to support the negative ; thelatter being laid thereou, and the sensitized paperon the negative. Tlie back is closed, the contact ; lieing m
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Keywords: ., bookcentury1800, booksubjectin, booksubjectmechanicalengineering
