152 DISEASES OF THE HORSE’S FOOT 
Where the breaks in the horn are so large as to prevent 
a level bearing 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 huflederhitt described in 
the treatment of pumiced sole. 
(b) Tot Sponey Hoor. 
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 
* Veterinary Journal, vol. iti, p. 71. 
