56 



THE POPULAR SCIENCE MONTHLY. 



the commencement of the ascending part of one step-curve belonging 

 to the right foot we will let fall upon the staff a perpendicular (a) ; 

 this line will determine the commencement of the pressure of the right 

 foot. A perpendicular (b) let fall from the end of the curve will de- 

 termine where the pressure of this foot ends. Between these two 

 points let us trace a broad white line; it will express, by its length, 

 the duration of the pressure of the right foot. A similar construction 



Fig. 10. 



made on line 1, from the succeeding step-curve, will give the notation 

 of the pressure of the left foot. The notations of the left foot have 

 been shaded with oblique lines, to avoid confusion. 



Between the pressure of the two feet there is found to be silence in 

 the rhythm ; that is to say, the expression of that instant of the course 

 when the body is suspended above the ground. 



If we note in this manner the rhythms of all the paces used by 

 man, we shall obtain a synoptical table which will much facilitate the 

 comparison of these varied rhythms. Fig. 11 represents the synop- 



Fio. 11. Synoptical Notation op the Four Kinds op Progression used by Man. 



tical, of the four kinds of progression, or paces, which are regularly 

 rhythmical, and in which the two feet act alternately. Line 1 repre- 

 sents the notation of the rhythm of the walking-pace. The pressure 

 of the right foot upon the ground is represented by a thick white 

 stroke, a sort of rectangle, the length of which corresponds with the 



