History of the Typewriter

Forfatter: Geo. Carl Mares

År: 1909

Forlag: Guilbert Pitman

Sted: London

Sider: 318

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— 34- Whilst Hall was working on his machine, Mr. Geoige House, of Buffalo, New York, produced, in 1865, a machine on quite novel lines. From the illustration it will be seen •that the types were arranged in a basket, striking up to a common centre, and the paper was wound round a cylinder, supported by a carriage. After the depression of a key the carriage did not move along laterally, as now, but revolved, as we have seen was the case in Thomas’s machine. There were forty-one keys, and the general idea seems to have been exceptionally good. The next step in the evolution of the writing machine was made by John Pratt, an American, at that time residing in London. In 1866 he took out a patent for a machine, afterwards exhibited before the members of the Society of Arts, in which he employed a. small plate of metal bearing the fount of letters arranged in rows upon it. This was supported vertically, and placed behind a sheet of paper held in a similar position. He provided means whereby the plate could be moved in any desired position, so as to bring the selected letter behind a small hammer. The depression of a key caused the plate to move to the required position, the hammer to strike the blow and the paper to shift along to make room for the next letter. This machine has passed into oblivion, but many years after, a later and very highly improved model was discovered, and after renovation and repair found its way into the national collection at South Kensington. The later instrument, of which two illustrations, representing the front and back views respectively, are presented, contains several very important features. In place of the type plate it carries a small typewheel, on which the letters are mounted in three horizontal and twelve vertical rows. This wheel is con- nected to a train of clockwork that tends to rotate it, but is prevented from so doing by means of a tooth mounted in a notched circular plate, placed at the foot of the vertical shaft of the typewheel. The shaft can thus be brought to rest at positions corresponding each to a single vertical row