152 DISEASES OF THE HOESE'S FOOT 



Where the breaks in the horn are so large as to prevent 

 a level l)earmg for the shoe being obtained, the interstices 

 should be filled up with one or other of the preparations 

 made for this purpose. One of the most suitable is that 

 discovered by M. Defay. By its means sand-cracks or 

 other fractures of the horn may be durably cemented up. 



' Even pieces of iron may be securely joined together by 

 its means. The only precaution for its successful applica- 

 tion is the careful removal of all grease by spirits of sal- 

 ammoniac, sulphide of carbon, or ether. M. Defay makes 

 no secret of its composition, which is as follows : Take 

 1 part of coarsely-powdered gum-ammoniac, and 2 parts of 

 gutta-percha, in pieces the size of a hazel-nut. Put them in 

 a tin-lined vessel over a slow fire, and stir constantly until 

 thoroughly mixed. Before the thick, resinous mass gets 

 cold mould it into sticks like sealing-wax. The cement 

 will keep for years, and when required for use it is only 

 necessary to cut off a sufficient quantity, and remelt it 

 immediately before application. We have frequently used 

 this cement for the repair of seriously broken hoofs. It is 

 so tenacious that it will retain the nails by which the shoe 

 is attached without tearing away from the hoof.'* 



Failing this, the bearing surface may be made level, and 

 fractures repaired by using the hujiedcrldtt described in 

 the treatment of pumiced sole. 



{h) The Spongy Hoof. 



Definition. — This is the opposite condition to the one we 

 have just described, and is characterized by the soft and 

 non-resistant qualities of the horn. 



Symptoms. — Spongy hoof is quite common in animals 

 that have large, flat, and spreading feet — in fact, the two 

 appear to run very much together. It is a common defect 

 in animals reared in marshy districts, and of a heavy, 

 lymphatic type. The Lincolnshire Shire, for instance, has 

 often feet of this description, and, the causative factors being 



* Vetennary Jotirnal, vol. iii., p. 71. 



