DISEASES FROM FAULTY CONFOEMATION 137 



turning the nut on the screw the clamps are brought towards 

 each other, and the crack thus prevented from spreading.'* 



Still a further useful clamp is that of Koster. This is 

 considerably broader than the clamp of Vachette, and its 

 gripping edges are provided with teeth (see Fig. 89). 



As with the clamp of Vachette so with this, a groove is 

 burned into the wall on each side of the crack for the 

 accommodation of the jaws of the instrument, and the 

 clamp itself pressed home by means of a special pair of 

 forceps. This form of clamp holds well, and has the 

 advantage of securing a wider area of horn than that of 

 Vachette or McGill. 



Fig. 89. — Roster's Sand-crack Clamp. 



Clamping by any method should be advised or under- 

 taken only under certain conditions. The horn should be 

 moderately strong, and the wall should, be thick. This 

 practically restricts the use of the clamp to cracks of the 

 toe, and it is there, as a fact, they are found of most 

 benefit. While burning the grooves for the clamp, and 

 while tightening the clamp itself, the animal's foot should 

 be on the ground and bearing weight at the heels, thus 

 insuring the greatest possible approximation of the edges of 

 the crack. 



With all methods of clamping an untoward result is 

 sometimes the formation of a fresh crack at the point of 

 insertion of the clamps. 



(c) By the Use of Thin Metal Plates. — These are of use 

 when the horn of the wall is too thin to allow of clamping, 

 and are therefore of especial use in cracks of the quarters. 

 * Veterinarian, vol. Ixi., p. 141. 



