ANIMAL MOTION. 



31 



means of a curve T\ hich readily allows us to study its phases. 

 We have fully explained elsewhere the nature of this in- 

 strument, the experiments for which it is suitable, and 

 the results which it gives.* At present we shall limit our- 

 selves to a summary description of the chief results of 

 myography. 



FIG. 2. The Myograph. 



In order to explain thoroughly the function of the appa- 

 ratus, let us reduce it in the first place to its essential 

 elements. Fig. 2 shows a muscle of the calf of a frog's leg, m, 

 suspended by a clip by means of the bone to which the upper 

 part of the muscle is attached. The tendon, t, of the muscle 

 has been cut and then tied by a thread to the lever, L, one end 

 of which can be raised or lowered while the other is fixed ; the 

 nerve, n, is susceptible of electric excitement, which produces 

 certain contractions followed by relaxations in the muscle, that 

 is to say shocks. Eacli of these movements of the muscle is 

 communicated to the lever, which is raised or lowered, ampli- 



* Du Mouvcment dans Ics Functions dc la Vie. Paris, 1S67 : G. Bailliere. 



