[ 8' ] 



fubftituted for the exhibitions and occultations of the lights; 

 even a fingle light or flag may be made to anfwer the" purpofe, 

 if any contrivance be annexed to lignify to the obfervcr when 

 the occultations which denote a letter are ended^ and alfo when 

 a word is finifhed-. 



Another method of transferring thefe fignals is by altering 

 the fituations of thcfc lights or flags, the plan of which will be 

 better underflood by a diagram than by any general defcription. 



The point F. fi.g. r. reprefents die place from which the in- 

 telligence is to be fent, and the point G that to which it is to • 

 be conveyed. In the horizontal line yi B, 24 points are aflTumed. 

 at equal intervals to reprefent the letters of the alphabet, and 

 marked as in the figure. When it is intended to fignify a fen- 

 tence or a word, lights by night, or flags by day, are to be fet 

 up in the points of the line which reprefent the fymbolical 

 letters that denote it, and the true pofition of thefe lights or 

 flags may be thus afcertained at the point G. Let there be a 

 pole ereSed at a convenient diftance from G in the line G F, as at 

 C, and a line D E parallel to A B be graduated as A B, and 

 marked as in the figure with the 2+ letters, the obferver at.G 

 moves his eye along the line D E until the edge of the pole C 

 is feen in the fame line with the light exhibited in the line JB 

 and the pofition of his eye in the line D E marks the letter 



Vol. VI. L,. fignified. 



