356 



m walking, and if the sight did not enable us to see, at a distance, the ob- 

 ject towards which we are moving, we should go to a considerable dis- 

 tance from it* If you place a man, with his eyes blind-folded, in the middle 

 of a square field, he will, in his attempt to get out, and thinking that he 

 is moving in a straight line, make for one of the corners. It is, almost 

 always, towards the left that we deviate* the right lower extremity, which 

 is the stronger, inclining the body towards the opposite side* Those 

 who are lame depart much more from a straight line, and deviate to- 

 wards the side of the shorter leg. The motions which they are obliged 

 to use, and which render their gait so remarkable, are occasioned by the 

 necessity of incessant and powerful efforts, to prevent the body from giv- 

 ing way to its own weight^ and to the greater power of the sound extre- 

 mity, which inclines it towards the affected side. 



The breadth of the feet, and a moderate separation of these parts, give 

 a much firmer support to the centre of gravity. Thus, in walking on a 

 moving and insecure surface, we hold apart our feet, so as to include a 

 greater base of sustentation. Those who have been long at sea, acquire 

 such a habit of holding their feet asunder, in the way they are obliged to 

 do during the rolling of a ship, that they cannot lose the habit, even when 

 on shore, and are easily recognized by their gait. A sailor is unfit for 

 active service* till he has acquired what is called* by sea-faring people^ 

 a seaman's foot, that is, till he is capable of stepping firmly on the deck 

 of a vessel tossed by the tempest. 



The gait of a woman, from her having smaller feet, is less firm ; but 

 ought we, from that circumstance, to infer, with the most eloquent wri- 

 ter of the eighteenth century, that this diminutive size of the foot, is con- 

 nected with the necessity of her being overtaken in flight? The concave 

 form of the soal of the feet, by enabling them better to adapt themselves 

 to the unevenness of the soil, concurs in giving a firmer footing in walk- 

 ing, and in other motions of progression. There is^ in walking, an in* 

 termediate moment, between the beginning and the end of a step, during 

 which the centre of gravity is in the air : this lasts from the moment whert 

 the centre of gravity is no longer in the foot which remains behind, till 

 it returns into the other foot which is carried forward. 



Walking is modified, according as it takes place on an horizontal or 

 an inclined plane j in the latter case, we ascend, or descend, and the ex- 

 ertion is much more fatiguing. To explain the action of ascending, let 

 us suppose a man at the bottom of a flight of stairs, which he wishes to 

 go up $ he begins by bending the articulations of the limb which he is 

 desirous of carrying forward ; he raises it thus, and shortens it to advance^ 

 and when the foot, which is in a state of semi-extension, rests on the 

 ground, he extends the articulations of the other extremity, carries thus 

 the body upward in a vertical direction, and completes this first step, by 

 contracting the extensors of the leg that were first in action, so that they 

 may bring forward and restore it to the centre of gravity to which the 

 posterior leg, whose foot is extended*, has given a vertical motion of ele- 

 vation. Hence, in ascending, the calves of the legs and knees, especially 

 the latter, are so much fatigued ; for, the effort with which the extensors 

 of the foremost leg, bring back again upon it the centre of gravity, is 

 tnore powerful than that by which the gemelli and the soleus impart to 

 it, by extending the hindmost foot, a motion of vertical elevation. 



To relieve the extensors of the leg, we bend the body forward, as much 



