XXXVIL] 



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.). 



FIG. 131. Chronograph arranged to Write on fc Horizontal Cylinder, as made by Verdin. 



FIG. 132. Marey's Simple Myograph, as made by Verdin. 



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

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



