XXXVII.] 



PENDULUM-MYOGRAPH. 



211 



Grove's cell. The analysis may also be done by means of the "automatic 

 break" arrangement attached to the revolving drum (Lesson XXXV.). 



J<'IG. 131. Chronograph arranged to Write on ft Horizontal Qyllnder, as made by Verdin. 



F/G. 132. Marey's Simple HfOgraph, as made by Verdin. 



6. Vibrating Eeed as a Chronograph. For measuring small intervals of 

 time this is very convenient. The arrangement was first adopted by Grun- 



