358 



MR. P. O. PEDERSEN ON THE SURFACE-TENSION OF LIQUIDS 



ends of which are the steel plates l\ and P^ The edges of these steel plates, k, are 

 knife-formed and effect the cutting of the jet, as described later. 



The "jet-catcher" itself is, as is shown in figs. 5-6, arranged on a pendulum C, 

 turning about the axis p-p. In order to vary the height of the pendulum the stands 

 A are furnished with a number of holes for the screws S, as shown in the figure. 

 The "jet-catcher" is fastened to the pendulum through the cross-piece t by means of 

 the screws * (see fig. 4). The exact position is secured by means of two cones i, 

 which fit in the corresponding holes in the cross-piece t. 



5cm. 



Fig. 7. 



The axis of the pendulum is arranged perpendicularly over, and parallel to, the 

 horizontal jet at such a height that the position of the jet in relation to the "jet- 

 catcher" is about as shown in fig. 6, where S indicates the jet. 



If the pendulum is caused to swing, the "jet-catcher," every time it passes the jet, 

 will cut out a portion of it. If the jet is perpendicular to the edges k, and parallel to 

 the plane through corresponding edges, the length of the piece that is cut out of the 

 jet each time is equal to the distance between the edges k. With a complete swing 

 (both forwards and backwards) the total length L of the portions of the jet cut off (see 



fig. 7) is 



L = L, + L 2 . . . (1). 



