72 
LAMENESS IN HORSES. 
with exudations of coagulable lymph in a state more or less ad¬ 
vanced towards assimilation to the altered condition of the mem¬ 
brane itself. Sometimes, in a more advanced stage of disease still, 
the membrane exhibits a sort of fibrous or reticular character, 
having running over its surface slender bands or cords of consider¬ 
able toughness, disposed after a manner to form so many little 
meshes or pouches upon the membrane. Within the cavity of one 
bog-spavined joint we examined, lodged in the upper and posterior 
compartment of it, we found a small parti-coloured ovoid body, in 
appearance not unlike the pineal gland of the brain, though not 
above half its magnitude, secured in its situation by slender cords 
of the same description as those first mentioned. The substance 
being cut in half, nought was found within it but some loose soft 
tissue resembling a mass of condensed cellular membrane. 
In some comparatively rare instances the thickened capsule of 
the joint, after the continuance of bog spavin for some length of 
time, becomes slowly converted into a solid and hard substance of 
the nature of callus or cartilage, and this, in the progress of the 
morbid action, changes into osseous substance; transformations 
which, as we have seen, Mr. Pritchard regards as taking place in 
the secreted fluid of the joint. This ossific action may, however, 
not confine itself to the region of bog spavin, but may extend over 
contiguous parts, and at last grow into a large spreading ugly tu¬ 
mour upon the inner side of the hock joint. 
Bog Spavin is not productive of Lameness so long as it 
maintains its ordinary form, or, in other words, so long as it con¬ 
sists merely in accumulated secretion and thickened capsule. Nor, 
in general, is there any reason to apprehend any thing further. 
Still, every now and then do we meet with cases in which bog 
spavin is growing into or has already become a formidable disease. 
Inflammatory action appears to be set up in the capsule of the 
joint; and those changes in the lining of the capsule, and in its 
secretion, which have been already detailed, supervening, the 
disease presents itself to us in the form of a tumour upon the 
inner side of the hock, spherical in its form, and of considerable 
magnitude, conveying heat to the feel and tenderness to pressure, 
which, from its producing lameness, and, perhaps, to a serious 
amount, peremptorily calls upon us for 
Treatment. Of what kind, however, will depend upon the 
state in which the hock is brought to us. 
Supposing that there is evidence of inflammation existing in it, 
even though that be of but an incipient or declining character, 
blood-letting, in as topical a form as practicable, had better, without 
loss of time, be had recourse to. We seldom do much good by 
opening any vessels about the hock for this purpose, and, therefore, 
