Although this article is a report about wire telegraph operator practices, many early radio operators came from the ranks of the wire telegraphers, and followed many of the same traditions. In particular, "ham" would evetually surface on the radio waves as an insult applied by commercial operators toward their amateur counterparts. This extract comes from the full text of Telegraph Talk and Talkers.
 
McClure's Magazine, January, 1902, page 231.

TELEGRAPH  TALK  AND  TALKERS.

HUMAN  CHARACTER  AND  EMOTIONS  AN  OLD  TELEGRAPHER  READS  ON  THE  WIRE.

BY  L.  C.  HALL.

THE  SLANG  OF  THE  WIRE.

    Like any other language, Morse has its patois--a corrupted version of the purer speech used by the inexperienced or by those to whom nature has denied the finer perceptions of timing and spacing. This patois might be called "hog-Morse." It would be quite impossible to give even a rude idea of the humor contained--for the expert--in some of the corruptions of which hog-Morse is guilty. These consist largely in closely joining elements which ought to be spaced, or in separating others that are meant to be close-coupled.
    In the patois of the wires "pot" means "hot," "foot" is rendered "fool," "U. S. Navy" is "us nasty," "home" is changed to "hog," and so on. If, for example, while receiving a telegram, a user of the patois should miss a word and say to you "6naz fimme q," the expert would know that he meant "Please fill me in." But there is no difficulty about the interpretation of the patois provided the receiver be experienced and always on the alert. When, however, the mind wanders in receiving, there is always danger that the hand will record exactly what the ear dictates. On one occasion, at Christmas time, a hilarious citizen of Rome, New York, telegraphed a friend at a distance a message which reached its destination reading, "Cog hog to rog and wemm pave a bumy tig." It looked to the man addressed like Choctaw, and of course was not understood. Upon being repeated, it read, "Come home to Rome, and we'll have a bully time." Another case of confusion wrought by hog-Morse was that of the Richmond, Virginia, commission firm, who were requested by wire to quote the price on a carload of "undressed slaves." The member of the firm who receipted for the telegram being something of a wag, wired back: "No trade in naked chattel since Emancipation Proclamation." The original message had been transmitted by senders of hog-Morse, called technically "hams," and the receivers had absent-mindedly recorded the words as they had really sounded. What the inquirer wanted, of course, was a quotation on a carload of staves in the rough.
    The mere sound of the styles of some transmitters is irresistibly comic. One of these natural humorists may be transmitting nothing more than a string of figures, and still make you chuckle at the grotesqueness of his Morse. It is an every-day thing to hear senders characterized as Miss Nancys, rattle-brains, swell-heads, or cranks, or "jays," simply because the sound of their dots and dashes suggests the epithets.