286 THE ARTISTIC ANATOMY OF ANIMALS 



indicated by the oscillations of the head. We will neglect 

 these. 



But this tracing, which serves us for an example, is not, 

 it must indeed be said, of very easy reading ; it would be 

 still less so if the paces of a horse were registered, for there 

 would then be four lines, the entanglement of which would 

 cause greater complication. 



These difficulties of reading need be no longer feared, if 

 we transform the tracing into a notation by means of the 

 following diagram. 



There are drawn (Fig. ii8) below the graphic tracing two 

 horizontal lines (i, 2). From the point where the line D 

 rises (commencement of the pressure of the right foot), and 



Fig. 117. — Tracing of the Running of a Man (after 

 Professor Marey.) 



D, Pressures and elevations of the right foot ; G, pressures and elevations 



of the left foot. 



from the point where this same line descends (end of the 

 same pressure), we let fall two vertical lines joining the two 

 horizontal ones mentioned above. At this plane, and 

 between the two vertical lines, we mark a broad white one 

 (a, h). This expresses, by its length, the duration of the 

 period of pressure of the right foot. In doing the same for 

 the line G, we obtain for the indication of a pressure of the 

 left foot an interval of the same kind, in which are marked 

 cross-lines, or which is tinted gray, in order to avoid all 

 confusion with the preceding tracing. 



This notation can, with sufficient exactitude, be compared 

 to that which is employed in the musical scale. The hori- 

 zontal lines I and 2 represent the cofupass. We there also see 

 notes ; these are the bars indicating the pressure, of which the 



