172 DISEASES OF THE FEET. 



to be relied upon with thick horn, the outside of which may be 

 practically healthy and char black, while its underlying surface 

 may be cankered. Having by means of the knife and cautery re- 

 moved every known particle of disease, the next procedure is to 

 13ack the surface of the sole and frog, thus exposed, with a powerful 

 astringent or caustic dressing. A great favourite of mine consists 

 of equal parts of sulphate of copper, iron and zinc, mixed with strong 

 carbolic acid, a very little vaseline being added to give the mass 

 cohesion. The dressing, covered by a pledget of tow, is held in 

 position by a shoe with an iron or leather sole, and the dressing 

 and the tow together should be of sufficient bulk to produce slight 

 pressure on the sole when the nails of the shoe are drawn up. . . . 

 On the second day following, the shoe should be removed and the 

 foot redressed. Commencing at the edge of the sound horn, as the 

 most dependent part of the foot, all new horn, no matter what its 

 condition, must be pared to the quick, especial care being taken 

 to effectually remove any lingering disease. . . . After all disease 

 has been excised, carefully clean the foot with Avaste, thoroughly 

 protect any raw surface resulting from over-cauterisation by some 

 mild agent, such as a saturated calomel ointment, re-apply an as- 

 tringent dressing (I would suggest spirits of turpentine with as 

 much iodoform as would dissolve in it) over the whole affected 

 surface, and nail on the shoe. This method of procedure should 

 now be thoroughly carried out daily for a time, and as it is pro- 

 ceeded with, a successful issue soon becomes assured in nearly every 

 case. When, in spite of these efforts, the disease still persists, 

 depend upon it, the fault is Avith the operator, who has failed to 

 eradicate some centre of infection. Under these circumstances it 

 may be necessary to re-cast the patient, re-pare the foot, and by the 

 aid of eye, knife and cautery endeavour to find the cause, and having 

 found it, which can invariably be done, remove it. The usual treat- 

 ment will then speedily be successful. As the case proceeds, dress- 

 ing every other day will soon be sufficient, then twice a week, and 

 finally once a week until completely cured. 



" During this healing process, and after the complete eradication 

 of canker, it may be again repeated. No agent seems to have a 

 more beneficial effect than calomel, and for this purpose it is best 

 used in dry powder. Under this dressing any remaining spot of 

 canker is readily detected by the wet condition of the calomel when 

 the shoe is removed next day. In dealing with such a spot, a very 

 good plan, after all apparently diseased tissue has been excised, is 

 to touch the cankered part with solid nitrate of silver, or a feather 

 dipped in one of the strong mineral acids, and then re-apply calomel 

 over the surface. In successful treatment the shoe must be re- 

 moved each time. An adjustable plate will not do, as no man can 



