Type Writers, mechanical contrivances for writing or printing with a system of movable types instead of a pen. They involve: 1, a position movement, for bringing type to a printing point; 2, an inking device; 3, an impression movement; and 4, a device for letter and line spacing. These elements have been combined in a variety of ways. The most primitive is that in which the types are engraved on a cylindrical bar, which bar is revolved on its axis and also moved backward or forward by the hand of the operator, to present the desired type to the common printing point. This bar is then depressed, thereby delivering the impression through a saturated ribbon upon a sheet of paper wrapped around a cylinder placed at right angles with the type-carrying impression bar. To the paper Cylinder a rotary and a longitudinal movement are imparted for the purpose of accomplishing the letter and line space. Nearly the reverse of this is the machine in which the types are arranged on a sliding rod or a narrow bed, and the impression is given by a bar or lever, the impression point of which is equal in size to the face of a letter. This machine was designed to form wax matrices for stereotype moulds, but can be used for printing by interposing paper and inking ribbon between the type and the impression bar.

A combination of the essential elements of these two machines was patented in the United States in 1868, the types being arranged on a plate in parallel rows, and the impression given by a plunger or striker. All necessary movements in this machine are accomplished by mechanical means, the operator being simply required to move or depress a key corresponding to the letter desired to be printed. Another class of type writers may be generally described as consisting of a letter wheel or disk, on the periphery of which the types are engraved, which type wheel is revolved on its axis for the purpose of presenting the desired letter to the printing point, after which either paper or wheel is moved to give the impression. Another method of type writing is by means of a section of a globe or hemisphere, having a series of perforations from circumference to centre, in which are placed sliding plungers. On the inner end of each plunger is engraved a type, and on the outer end, upon a button or knob, the corresponding letter. These plungers are directed toward a common centre or printing point, and the paper is fed past this point to produce the letter and line space.

The principal mechanical device of another type-writing machine consists of an arrangement of key levers of varying lengths, which levers are made to pass each other and present their type-bearing ends at a common printing point. - The Sholes and Glidden type writer consists of a series of swinging type bars of equal length, pivoted on the circumference of a circle, in such manner that their type-bearing ends, when brought to the printing point, will strike at the centre of the circle. By this means a series of type bars of uniform length are caused to present their type at a common printing point. The paper is fed past this point, to accomplish the letter and word spacing, by the longitudinal movement of a paper car, bearing a cylindrical platen, which platen is moved upon its axis a certain distance to accomplish the line spacing. The movement of the paper car past 'the printing point is effected by a spring escapement, and governed by a bale or lever which is moved by the depression of any key. Fig. 1 represents a front view of the Sholes and Glidden type writer, with working parts exposed.

A saturated inking ribbon is interposed between the type and paper, and is moved automatically through the slots shown on each side of the disk. - A type writer recently invented by L. S. Orandall of New York consists mainly of a vibrating platen and paper feed arranged in connection with a series of type bars, which are provided with more than one type and operated by oscillating finger levers in such manner that, according to the backward or forward motion of the same, two adjoining types are printed on a common centre. The number of centres may be increased, in proportion to the number of types on the bars, by definite vibrations of the platen. For example, if there are six types on a bar, two of them are brought to the printing point in the manner above stated, and to utilize the Remaining four one forward and one backward vibration of the platen is required. The types are placed on eight bars, arranged in the segment of a circle, and connected with eight finger cups by oscillating levers. Two thumb keys, with connecting mechanism, effect the transverse movements of the platen. The longitudinal movement of platen, for accomplishing the letter space, is by common means.

This machine, being operated by the Augers without changing position of hands, may be used by the blind with facility, but the reading requires sight. In fig. 2, 1 represents a side elevation, showing the arrangement of its principal elements; 2 and 3 are detail side views of the finger lever and type bar, showing their duplex motion. The type bars A are so connected with the finger levers B, and stationary supporting arms C, that a double action may be imparted to them simultaneously with their swinging motion toward the printing points. The double action throws the lever a fixed distance in a forward or backward direction, and thereby admits the use of two types on each type bar for each printing point or centre. The double action of the type bar is produced by projecting cams or shoulders, D, which, by the forward or backward oscillation of the finger levers, are thrown into contact with corresponding projections or recesses, E F, of the fixed arm 0, so as to define the extent of movement required for the coupled pair of types to strike their printing point on the platen, G. - In the "Zachos steno-phonotype reporter " the types are placed on twelve shuttle bars, according to a definite scheme, and two or more of the bars may be placed in position simultaneously.

The impression is given by a plunger or platen common to all the shuttle bars. By his scheme any monosyllabic word of the English language may be produced at one impression.

Sholes and Glidden Type Writer.

Fig. 1. - Sholes and Glidden Type Writer.

A. The bank of keys. B. Type-lever disk, showing one lever in printing position. C. Space bar. D. Space bale and yoke. E. Wheel and axle for return of paper car. F. paper car turned back upon its hinge to expose printing.

Crandall's Type Writer.

Fig. 2. - Crandall's Type Writer.