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Ακτη επι προβλητι, νεηνιη ανδρι εοικως
not possibly have been attained without it. But, not to rest on presumption alone, the instrument (Abortf«) is expressly mentioned by Polybius, and in language which implies it to have been, in his time at least, in common ordinary use: after noticing in his tenth book two imperfect methods of conveying military signals to a great distance, he gives a somewhat detailed description of a third, in terms which are thus rendered by his translator, Nr. Hampton. “ Take the alphabet and divide it into five parts with five letters in each: in the last part indeed one letter will be wanting ; but this is of no importance: then let those who are to give and to receive the signals write upon five tablets the five portions of the letters in their proper order, and concert together the following plan ; that he on one side who is to make the signal, shall first raise two lighted torches and hold them erect till they are answered by torches from the other side: (this only serves to shew that they are on both sides ready and prepared,) that afterwards, he again who gives the signal, shall raise first some torches upon the left hand, in order to make known to those on the other side which of the
tablets is to be inspected; if the first, for example, a single torch; if the second, two, and so of the rest; that then he shall raise other torches also upon the right, to 'mark in the same manner to those who receive the signals, which of the letters upon the tablet is to be observed and written : when they have thus regulated their plan, and taken their respective posts, it will be necessary first to have a dioptrical instrument framed with two holes or tubes, one for discerning the right, and the other the left hand of the person who is to raise the torches on the opposite side, (δεησει πρωτον μεν διοπτραν εχεις δυο αυλισκες εχεσαν, ως τε τε μελλοντος αναπυρσευειν, τω μεν τον δεξιον τοπoν, τω δε τον ευωνυμον θεωρειν.) the tablets must be placed erect, and in their proper order, near the instrument; and upon the right and left there should be also a solid fence, of about ten feet in length, and of the height of a man, that the torches, being raised along the top of the ramparts, may give a more certain light, and when they are dropped again, that they may also be concealed behind them: when all things then are thus prepared, if it be intended, for example, to convey this notice that some of the soldiers, about a hundred in number, are gone over to the enemy: it will be necessary in the first place to choose words for this purpose, which contain the fewest letters: thus, if it be said, Cretans a hundred have deserted; the same thing is expressed in less than half of the letters which compose the former sentence: the words then, being first written down, are communicated by the means of torches in the following manner; the first letter is Cappa; which stands in the second division of the alphabet, and upon the second tablet; the person, therefore, who makes the signal, first holds up two torches upon the left, to signify that it is the second tablet which is to be inspected; and afterwards five upon the right, to shew that Cappa is the letter which he who receives the signal, must observe and write; for Cappa stands the fifth in the second division of the letters ; then again, he holds up four torches upon the left, because Ro is found in the fourth division, and two upon the right, to denote that it stands the second in that division. From hence the person who receives the signal, writes Ro upon his tables, and in the same manner all the rest of the letters: by this method an account of every thing that happens may be conveyed with the most perfect accuracy."
In one of those dissertations, mentioned in the preface to the first volume, to have been printed and given away about seven years ago, (the one in question is dated the 19th Sept. 1804,) I expressed myself in the following terms.
66 This remark of Polybius may be premised, that the description, by way of digression, of such matters as those now under discussion, deserves to be considered as one of the most useful parts of a well composed history. But Polybius, like the rest of the classics, only conveys valuable information when his ostensible statements have been submitted to the test of the argument ex absurdo: for instance, the observation just cited is taken from his method of conveying intelligence to great distances by signals, and what can be more absurd than the dioptrical instrument he mentions there, which is to have two holes or tubes, one for discovering the right, and the other the left hand of the person who raises the signals. If, however, instead of the instrument he requires, we understand two common telescopes, (for it appears clearly from hence, as from a thousand other necessary inferences, that the ancients were acquainted with those dioptrical instruments,) and such two telescopes to be directed to opposite points of communication, we shall, by further unravelling his statement, have a plain description of the modern telegraph.”
In the course of the next year, (1805,) the late Mr. Dutens, viewing the passage above cited from Polybius in the same light as it had happened to me to do, expressed himself in his treatise Sur l'usage des Voútes chez les Anciens in the follow
ing manner. “ Le télégraphe, pretendu decouvert en France, n'est que la communication des signaux, indiquée par Polybe, et combinée avec celle dont parle Végèce. Ces deux auteurs renferment le principe et la manière d'opérer du télégraphe François.-Polybe propose une manière de faire usage des lettres d'alphabet, indiquée chacune par de certains signaux, faits avec nombre de flambeaux ou de torches. Il parle même du premier signal à faire, pour avertir le télégraphe prochain de donner son attention, et du signal de réponse à donner que l'on est prêt.
Sans doute, qu' aux signaux faits avec des torches ou flambeaux (du tems de Polybe) on avoit substitué depuis, des signaux faits avec bâtons ou de planches : car Végèce, qui vivoit au quatrième siècle, parle de cette manière de télégraphe comme etant si bien connue de son temps, qu'il juge inutile de la decrire, mais se contente d'en faire ment on dans les termes que nous ferions pour parler à présent du télégraphe employé en France et en Angleterre. (Vegetius, lib. 3, ch. 5. Aliquanti in castellorum, aụt urbium turribus, appendunt trabes : quibus, aliquando erectis, aliquando depositis, indicant quæ geruntur.)
This account of Vegetius is certainly clear and explicit, and points to the telegraph, as now in