\94f , DESCRIPTION OF A. TELEGRAPH USED IN SWEDEN, 



Advantages of gave the preference, becaufe it occupied lefs fpace, was more 

 b^the^hor. ra P^ anc * ea fy m " s move menls, more certain and unequivocal 



to the fight, and, to all its other advantages, added that of 



being ufeful by night. 



Defcription of the Machine. 



Defection. a, b, c, d, e, f, (Fig. 1, PI. XII.) is a frame of wood, in the 



openings of which are placed ten mutters at equal diflances 

 from each other, in three vertical ranks, that in the middle 

 confiding of four (nutters. Thefe (butters, which mould be as 

 thin as poffible, may be made of wood, iron or copper, and 

 are fixed on an axis on, the extremities of which move in holes 

 made in the frame. On the axis on, perpendicular to its di- 

 rection, but with an angle of 45° to the furface of the fliutteF 

 is a fmall arm ms, from one extremity of which a firing de- 

 fcends to the bottom of the frame, by means of this and of the 

 arm ?ns, the (hutter receives at pleafure a vertical or horizontal 

 pofition. Fig. 1 reprefents all the (hutters in a vertical pofi- 

 tion, and Fig. 4 (hows the profile of the machine, the (butters 

 being horizontal. It will be eafily feen, that when the (hutters 

 which are very thin, are obferved from a diftance and horizon- 

 tally, they will be fcarcely perceptible ; but they become vi- 

 fible, if, by drawing the firing s k, a vertical pofition is given 

 to them. When the machine is at reft, the (hutters are kept 

 in a horizontal pofition by a weight q attached to them at /, 

 and are fupported by the pin p I. In the other pofition they 

 are kept upright by a piece of wood p place behind them, but 

 which is mown in front in the plate. To prevent the firings 

 from getting entangled, the arms ms are fixed at unequal dif- 

 tances from their refpe&ive (hutters. The (Irings pafs through 

 holes made in the crofs plank ur, or uuu, (Fig 2.) which 

 (hows the plan. They may then be made to pafs through the 

 plank wxv, and be fecured to ten rings tt, each correfponding 

 to one finger, by which means a fmall machine may be conve- 

 niently worked. 

 Number of its According to this conftruction, 1024 combinations or dif- 

 iTgnah. tin6t fignals may be formed by raifing or lowering the (hutters. 



The better to diftinguifii them they are exprefled by numbers 

 on the following principle. Leaving out the upper (hutter A, 

 the machine will confift of three vertical lines, with three (but- 

 ters on each. To the upper (butter of each line give the value 

 4 of 





