600 'IHE DISEASES OF THE HORSE 



of pressure, or a part of it, becoming gradually accustomed to the amount 

 Avliich it will have to bear when the bar shoe is discontinued. In the mean- 

 time a little of the following lotion ma}' be applied daily to the situation of 

 the corn by means of a feather : — 



Take of Chloride of Zinc 1 tliaclnii. 



Water G ozs. 



Glycerine 2 ozs. Jlix, 



In every case the bar shoe must be continued until tlirlicd of the crust and 

 the bar grow down strongl}- ; and then a common shoe may be applied, as 

 directed in Chap, xxxviii. 



SANDCRACK 



In the anatomical description of the foot, at page 383, it will be seer 

 that the crust is composed of fibres, running pai-allel to each other in i 

 direction from the coronet to the ground surface These fibres are glued 

 together firmly in a sound and strong hoof; but, in a weak one, it some- 

 times happens that the gelatinous matter is not in sufiicient quantity, and 

 then the fibres separate, and leave a crack of greater or less extent, accord- 

 ing to circumstances. This, called a sandcrack, happens at the thinnest 

 part, which is the inner quarter in the fore-foot, and the toe in the hind. 

 7'o cure it, the foot must be rested, or at least that part of it where the 

 crack occurs, which in the fore-foot may be effected by the use of a bar 

 shoe, throwing the pressure entirely on the frog, as recommended in the last 

 section on corns, and taking care that the crust behind the crack is not in 

 contact with the shoe. By adopting this plan, I have succeeded in curing 

 sandcracks during moderate work ; but if it happens in the hind-foot, com- 

 plete rest must be given, as the toe cannot be I'elieved by any possible con- 

 trivance. The next thing to be done is to open the crack slightly, so that 

 any grit getting into it shall not cause its further expansion ; and in doing 

 this, if there is any little cellular cavity, it should be exposed. If the crack 

 extends to the coronet, a V-shaped groove should be made in the hoof with 

 the firing-iron, the apex pointing to the ground and the lines terminating 

 on either side of the breach in the coronary band. A mild blister may 

 from time to time be applied to the coronary secreting surface, when the 

 hoof may be expected to grow down and the crack gradually disappear. 

 The Y has the effect of diverting concussion from the w'eakcst spot. The 

 jar can also be reduced by cutting out a little hollow at the other end 

 of the crack. In this way horses may be kept at work while the new 

 material is forming. It takes about a year to grow down, but horses vary 

 much in the rapidity with which their hoofs grow. 



To prevent falling in or lapping over of the- edges, a wedge is sometimes 

 fitted into the space, and Mr. South, of Now ]>ond Street, London, has in- 

 vented an ingenious contrivance for the purpose. 



