\96 



DESCRIPTION OF A TELEGRAPH USED IN SWEDEN. 



completing the feries in each direction until the whole number 

 of combinations are expreffed, and tilling up the vacancies be- 

 tween the double row of numbers with fuch letters, figures, 

 words or fentences, as may have been previouily agreed upon, 

 its ufe by night. The two rows of numbers are only neceflary when the tele- 

 graph is intended to be ufed by night as well as by day, in 

 which cafe it mult be obvious, that when the concerted fignal 

 is made by raiting the mutters, thofe lights which ate placed 

 behind them, as will be defcribed hereafter, become hid, and 

 the value of the fignal is reverfed in confequence of the open 

 fpaces being vifible inflead of the clofed ones. 



A fecond table muft alfo be formed to contain the fame feries 



with the letter A prefixed as defcribed above. 



The correfpond- When the correfpondence requires fecrecy, the fignifica- 



ence may be tions of thefe numbers, and the methods of eftimating their 



value may be varied almoft to infinity by any one verfed in the 



knowldge 



