582 OPERATIONS ON THE FOOT. 



miiltiplication in the same direction of the said cells. When the 

 podophyUous tissue is inflamed, whether exposed or not, its latent 

 activity soon manifests itself. It gives rise to a great quantity of 

 hard horn, hollowed, as seen by Gourdon, with tubes, and obUque 

 in a direction backward. These tubes, more irregular than those 

 of the normal wall, are disposed in a parallel series ; they are in 

 form round, villo-papUlse, which have developed on the face border 

 of the laminEB. In these cases of production of horn by the action 

 of the podophyUous tissue alone, one never sees, between the 

 sensitive laminse, distinctly formed horny laminae in the middle of 

 the other cells, as it is observed in the wall proceeding from the 

 coronary band. The horn which rises on the surface of the 

 podophyUous, immediately after the removal of the piece of the 

 waU, is not a permanent one ; it must be replaced by the horn 

 of the coronary band. This change is complete, microscopical 

 examination proving that the wall which descends from the 

 coronary band, provided with keraphyUous laminae, engages itself 

 under the temporary wall, and sUdes by the action already 

 described over the surface of the soft ceUs of the laminated tissue. 

 As soon as this tissue, modified by inflammation, is covered over 

 by the permanent wall, its papiUae become atrophied, and its action 

 returns to the limited boundaries of physiological condition. — 

 {Chauveau.) 



The foot is an organ of support and an apparatus of elasticity; 

 it is through it that the whole animal machine maintains its rela- 

 tions with the ground, and that it adapts itself in its various move- 

 ments, so to speak, to its roughness. It is this that, as a last 

 spring, distributes and modifies the force of aU the movements of 

 the homy mass of the body, whose columns, the legs, may be 

 considered as the resultant. Intermediate with the body and the 

 ground, the foot transmits all the actions of weight reaching it, 

 and also between the body and the sensorium, toward which all 

 sensations resulting from its contact with surrounding external 

 substance return, the foot then becoming at the same time an organ 

 of feeling. To adapt it to this triple formation, nature has given 

 to it three properties, in appearance incompatible with each other, 

 which has, however, harmonized, viz.: first, a very great external 

 hardness, due to its horny envelope ; second, a certain amount of 

 flexibility, the combined result of the physical properties of its 

 cortical envelope and of its mechanical disposition of its different 



