WALKING. 



119 



ference of the pubis towards the right, the depression will 

 express a deviation of this point towards the left. 



The experiment gives the curve O V h (fig. 22) for the 

 tracing of the horizontal oscillations. It is first to be ob- 

 served that the number of these oscillations is only half that 

 of those which take place in the vertical direction ; so that 

 the body is carried towards the right side at the moment of 

 the maximum of elevation, which corresponds with the middle 

 of the pressure on the right foot, and towards the left at the 

 middle of the pressure on the left foot. This lateral sway- 

 ing of the trunk is the consequence of the alternate passage 

 of the body into a position sensibly vertical over each foot. 



If we would give an idea of the true trajectory of the pubis 

 under the influence of these two orders of oscillations com- 

 bined with forward movement, we must construct a solid 

 figure. With an iron wire bent in different directions, we 

 may illustrate very clearly this trajectory. Fig. 23 is inteuded 

 to represent the perspective view of this twisted iron wire ; 

 but we can scarcely expect the reader to comprehend clearly 

 this mode of representation. 



Fig. 23. — Attempt to illustrate, by means of a metallic wire, the simious 

 trajectory passed through by the pubis. To understand the sketch of 

 this solid figure, we must suppo.^e the wire to be close to the observer 

 at its left hand extremity, while it is removed from him at the right ex- 

 tremity. The amplitude of the oscillations has been greatly exaggerated 

 to render them more intelligible. 



In short, according to the formula of Mons. Carlet, the 

 trajectory of the pubis may be inscribed in a hollow half- 

 cylinder, with its concave portion upwards, at the base of 



