256 



General Mechanics. 



NIL :.l 7:1:1 



51793. 1:13. 



51 794. 1 : 7. 



51796. 1:18. 



51.793. Fall Apparatus (Kottenbach's), Figure (Ztschr. f. d. phys. u. chem. U., 18. s fl - 

 1905, p. 79) 5.10.0 



The time of vibration of a slowly vibrating plate spring serves as a measure for the time of 

 fall of an iron ball. In its passage through the position of rest the spring itself releases the ball by means 

 of the electromagnetic release, and at certain heights of fall the ball encounters the spring again in 

 passing through the state of rest, this being annunciated by an electric or mechanical signal. 



When ordering kindly state whether Electric or Mechanical Signalling is desired. 



51.794. Fall Apparatus for Free Fall (Edelmann's), for use with the v. Beetz Tuning Fork 

 Chronograph, Figure, without Tuning Fork Chronograph (No. 51,730) 6. 5.0 



At the commencement and end of fall a freely falling ball opens two currents divided by an ; 

 induction apparatus. The induction sparks determine the time-measuring tuning fork curves. Height 

 of fall of ball adjustable from 1 60 cm. 



51,705. Tuning Fork Chronograph (v. Beetz's), see Fig. 51,730 7.10.0 



51.796. Fall Machine (Morin's), Figure, perfectly constructed, for indicating the para- 

 ixila of fall, for ascertaining the acceleration and testing the law of velocities (Chwolson, 

 Lehrb. I, Fig. 211; Fr. phys. Techn. I, 2, Fig. 2234; Gan.-Man. Fig. 33) 18. 0.0 



51.797. Fall Machine (F. C. G. Miiller's) (M. T., Fig. 36), with electromagnetic-ally driven 

 tuning fork, for recording the vibration curve on a blackened glass disc. The tuning 



fork can also be used by itself 4. 0. 



:> 1,79*. Fall Machine for Free Fall (Pesograph, Lapsometer), Figure (M. P. I, Fig. 83 



[81]; Friek phys. Tc-chn. I, 2, Fig. 3456 [I, Fig. 500]) 13. 0. 



An oscillating pen records the vibration curve on a falling plate covered with paper. 



cl. 



