ON THE NAVICULAR DISEASK. 27 



tics. The heels are high, the sole strong, and the 

 crust thick, particularly at the toe ; but it sometimes 

 loses its due proportion of obliquity, and becomes 

 rather more upright than natural. There is, how- 

 ever, a more certain indication which usually pre- 

 sents itself; viz., a falling in of the inside quarter, 

 or slight indentation about the middle of the crust 

 towards the heel : this sometimes assumes the ap- 

 pearance of a stricture, in a slight degree, all round 

 the crust, and occasionally two or three of these 

 strictures or rings are apparent. 



Thus much may be observed without the removal 

 of the shoe ; but the protrusion of the frog within 

 the foot (adverted to in my former paper), together 

 with the morbid concavity of sole, may not be dis- 

 coverable till the drawing-knife has been exten- 

 sively employed, not only on the sole, but in exca- 

 vatino; those channels or commissures on each side 

 of the frog, between it and the bars. An inordi- Diminisiied 

 nate growth of sole and other parts of the foot, by oi t.u concealed 

 presenting prominent suriaces, too oiten conceal exterior. 

 from our view the encroachments and consequent 

 diminution of the horny cavity. The outer surface 

 of the sole of such a foot sometimes resists the 

 drawing-knife like a stone, from its excessive hard- 

 ness. 



I contend, that the navicular joint disease is ge- 

 nerally, though not always, preceded by one of these 

 contractions of the hornv box. It raav be the oe- 



