0, 1, 2, 3, 4, 5, 6, 7.
So that seven thousand different combinations are formed, of four figures each, which refer to a dictionary of words that are referred to,—of lists of the navy, army, militia, lords, commons, geographical and technical terms, &c., besides an alphabet. So that everything one wishes may be transmitted with expedition.
By night, white lights are used.
Dr. Darwin to Mr. Edgeworth.
Derby, March 15, 1795.
Dear Sir,—I beg your pardon for not immediately answering your last favor, which was owing to the great influence the evil demon has at present in all affairs on this earth. That is, I lost your letter, and have in vain looked over some scores of papers, and cannot find it. Secondly, having lost your letter, I daily hoped to find it again—without success.
The telegraph you described I dare say would answer the purpose. It would be like a giant wielding his long arms and talking with his fingers; and those long arms might be covered with lamps in the night. You would place four or six such gigantic figures in a line, so that they should spell a whole word at once; and other such figures in sight of each other, all round the coast of Ireland; and thus fortify yourselves, instead of Friar Bacon's wall of brass round England, with the brazen head, which spoke, "Time is! Time was! Time is past!"
MR. EDGEWORTH'S MACHINE.
Having slightly mentioned the contrivances made use of by the ancients for conveying intelligence swiftly, and having pointed out some of the various important uses to which this art may be applied, I shall endeavor to give a clear view of my attempts on this subject.
Models of the French telegraph have been so often exhibited, and the machine itself is so well known, that it is not necessary to describe it minutely in this place. It is sufficient to say that it consists of a tall pole, with three movable arms, which may be seen at a considerable distance through telescopes; these arms may be set in as many different positions as are requisite to express all the different letters of the alphabet. By a successive combination of letters shown in this manner, words and sentences are formed and intelligence communicated. No doubt can be made of the utility of this machine, as it has been applied to the most important purposes. It is obviously liable to mistakes, from the number of changes requisite for each word, and from the velocity with which it must be moved to convey intelligence with any tolerable expedition.