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The Telegraphic Code, now so essential an adjunct to the foreign correspondence department of every businesshouse, may be regarded as the legitimate and lineal descendant of the curious and complicated Cipher by whose aid the statesman of a past age secured his correspondence from the gaze of the unauthorised. But while the principal object of the cipher was secrecy, the objective point of the compiler and user of the telegraphic code is economy, though considerations of strict privacy are not lost sight of.
The necessity for some means of minimising the heavy cost of cable despatches is one of those self-evident propositions that require no [380] emphasising. But for the telegraphic code, the cable would be as inaccessible to thousands of business people as the phonograph or any other of the high-priced developments of electric science. Yet is is an every-day occurrence for the officials at the cable offices to encounter members of the trading community to whom the existence of such an economiser as the telegraphic code comes as a surprising revelation. Cable clerks tell many amusing stories illustrative of the mingled prejudice and distrust manifested towards the use of a code by some people. There are many old-established mercantile houses, spending yearly hundreds of pounds on telegraphic communication with distant parts of the world, more than half of which might be saved by employing a code. But, from motives of old-fashioned conservatism, so difficult for the modern progressive mind to sympathize with, the principals prefer to adhere to the fully worded message, fondly believing that the extra length and cost will somehow ensure an immunity from mistake which they cannot conceive to be compatible with a message couched in few but meaningless trisyllables.
The constructive principle of an ordinary telegraphic code is very simple. The volume —n ecessarily large — consists of a collection of phrases and parts of sentences likely to be needed in framing a message. These phrases range from such essential colloquialisms as, 'I am not able' — 'If you are' — 'Has just arrived' — 'To-morrow afternoon' — to a lengthened description of the parts of a ship, engine, or machine; names, quantities, and qualities of goods, or of any subject on which business people may find it necessary to use the cable. These sentences are arranged in dictionary order, and to each one is attached an arbitrary word, also running in alphabetical sequence for facility of reference. In coding a message, the sender first writes it out in full, then looks up in the code those phrases which most nearly express the same meaning, noting the code word standing for each particular phrase. A message would be made up somewhat as follows: 'We are not able to (accuracy) complete work in time (sardonic). Can you allow us (emulated) fortnight longer (estuaries).' The words in parentheses representing the phrases that precede them would be telegraphed, thus reducing a message of fifteen words to one of four — plus address. The saving in transmitting, say, to the Cape, Calcutta, or Melbourne at about eight, four, and nine shillings per word respectively, is too obvious to call for comment.
Nearly every leading business has its own code, specially adapted to its requirements. Shipping people generally use Scott's, a bulky volume, in which is to be found probably every phrase of combination of common phrases likely to be needed in cabling despatches appertaining to shipping matters. A long message advising the owners of an accident to a vessel, detailing the parts damaged, extent of the injury, time and place of the occurrence, with probable cost and duration of repairs, may be cabled with two or three code-words. By the use of the Mining Code, another remarkable and exhaustive work, an engineer in Mexico can with two and even one word give his employers a detailed report of the progress of work, or describe with minuteness and accuracy a piece of required machinery. A popular code used by London stockbrokers enables their New York correspondents to keep them informed of the fluctuations of over forty or fifty leading American stocks in a message of three or four words only.
The ingenuity displayed by code-compilers in condensing a mass of detail into one word is often well-nigh marvellous. This species of code is known as the Combination. Its principle consists in dividing a subject into parts, giving each a number, then combining these several small numbers into one large one, and cabling it by means of its signal-word. Suppose, for example, the subject be an announcement of the arrival of a ship at a distant port, with a few details of the circumstances. The page of the code-book devoted to arrivals would be divided into, say, five columns. In each column are written ninety-nine phrases applicable to possible circumstances. Column 1 would contain the names of all the ships belonging to the firm, each being identified by a two-figure number (01 to 99). The second column would contain 99 phrases descriptive of some fact connected with the arrival, such as, 'Arrived two hours overdue,' 'In tow of harbour tug.' Each of the remaining columns is filled by likely phrases, similarly numbered, yielding 396 distinct statements regarding any one of the 99 vessels. In transmitting his message, the sender would pick from each column in turn a suitable sentence. Thus, from column 1, line 17, he would get the name of the vessel, Seagull; Column 2, line 21, 'Experienced bad weather; starboard lifeboat stove in;' column 4, line 37, 'Captain hurt, not seriously;' column 5, line 16, 'Ship leaves to-night.'
When this long report gets upon the cable, it is the very abbreviated form of two words, 'elegantly buccaneer.' The receiver on consulting his code finds that the first word stands for 17,142; the second, for 13,616. He ticks these off into five groups of two figures each, and is thus supplied with the numbers of the five sentences that make up the message.
The demand for telegraphic codes should be very large, in view of the number published. The catalogue of a leading publisher who makes a specialty of codes contains a list of some hundreds of distinct works. In addition to this, a large business is done by several firms who supply private codes specially constructed to suit particular needs and businesses.
As might be supposed, inventors make strenuous efforts to produce the 'briefest and most economical code published;' and if the state[381]ments of rival authors may be relied upon, there are many volumes in the market that possess this qualification. Unfortunately, extreme brevity is rarely compatible with accuracy; and it is an axiom in code construction that the greater the conciseness, the greater the task both of framing and translating a message.
The compiler of a really reliable and comprehensive code is met at the outset of his undertaking by a difficulty that, so far, has defied all attempts at solution beyond a certain point. Despite the fact that the rules of the cable companies permit him to lay under contribution eight languages, the total number of words that can be used for coding purposes is only about 150,000. The reasons for this are twofold. First, the companies decline to permit the use of any code-word of more than ten letters; and it is dangerous to employ those having less than seven, owing to the difficulty of detecting an error in short words. Further, thousands, nay, hundreds of thousands of words are rejected because of the similarity of the telegraphic symbols that make up the letters. Figures are rarely telegraphed; the possibility of noting an error in a group of arbitrary figures is very remote. Should a letter or two be 'jumbled' in a code-word, there are various ways of correcting the mistake — the sense, the context, and reference to the code; but these guides do not apply to the case of figures. The only remedy for a suspected error is repetition of the message at an enhanced cost of fifty per cent. Numbers, therefore, are expressed by a code-word. Errors in the transmission of amounts of money are very rare. A banker's code contains words for every possible sum of money from one halfpenny up to hundreds of thousands of pounds; and the authors have exhibited great ingenuity in making a limited supply of words do very extensive service.
The advantages of a telegraphic code are often let pass by the general public, owing to the supposition that it is necessary for the receiver of a coded message to possess a copy of the code used. This is not always the case. Most of the cable companies will permit the use of their private codes on payment of a fee generally equal to the cost of telegraphing one or two words. They translate the message into code language — which may necessitate a slight variation on the original text — and transmit it to the station nearest the addressee, where the clerk retranslates it into its original form.
In their early days, some of the cable companies exercised a very shortsighted policy towards the users of codes. By imposing numerous vexatious restrictions, they attempted to compel the public to transmit their despatches in a fully worded form; and even now, one or two companies frequently exercise their right to demand the production of the customer's code-book before consenting to put a cipher message upon the wire. But experience is gradually convincing them that it is to their interest to facilitate instead of restricting the use of the cable, since the cheaper the rates, the greater the bulk of business they will have.
The cheapness of telegraphic despatches in Great Britain renders the use of a code unnecessary, except when secrecy is an object; consequently, code messages do not cause much trouble to our post-office clerks, as they occasionally do to the officials of the cable offices.
12 august 04
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