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We prove that if two linear codes are equivalent then they are semi-linearly equivalent. We also prove that if two additive MDS codes over a field are equivalent then they are additively equivalent.

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Electrical transmission of handwriting has engaged a certain amount of attention ever since telegraphic transmission of printed characters was successfully carried out.As early as 1 886 Cowper and Robertson brought the writing telegraph' into a fairly operative form. This instrument was adapted to operate several receivers in series in " reporting " service, where the regular news ticker service was unobtainable or too expensive. The system was put to some use, chiefly in Pittsburg and vicinity.The writing was received on a paper tape, advanced at constant speed by clockwork. No pen-lifting device was provided and the words were connected together by a mark of the pen, mnaking figure work poor. As the characters were formed by the combination of the pen motion and the tape motion, a certain amount of practice and skill was required to produce a legible message.The electrical features were as follows: two independent variable currents were obtained from the transmitter; these passed over lines to the receiver where they traversed two electromagnets set at right angles to each other, and so influenced their effect upon a common armature as to cause tlhe receiver-pen rod to reproduce the motion of the transmitter pencil.It will be noted that this principle is nearly identical with that of Gruihu's Telechipographb2 recently described in the technical press, the main differences being that the telechipograph 1. Wm. Maver, Jr., American Telegraphy.

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