140 



my noviciate at the Royal Veterinary College, it was my priv- 

 ilege to witness numerous dissections of Stringhalt subjects, 

 and presumably to learn all that was then known upon the 

 etiology and pathology of that disease. 



NOTES AND QUERIES. 



The following is the substance of some of the notes which I 

 took of the lectures by Professor Spooner upon this subject. 

 They may prove interesting to the student of hippedo pathology. 

 There is a vital contractile force in involuntary muscles which 

 is entirely independent of, and distinct from the force which is 

 subservient to the influence of the will. Mechanical pressure 

 alone would produce pain. Stringhalt as a rule only affects 

 the hind extremities, although Professor Spooner has seen an 

 instance of a peculiar jerking action of one fore-leg, which he 

 considered to be a true case of Stringhalt. 



PECULIAR MECHANISM OF THE HOCK-JOINT. 



The mechanical construction of the astragalo-tibial articula- 

 tion, the principal articulation of the hock joint, explains in 

 some measure the jerking action peculiar to, and diagnostic of, 

 this disease. One effect of the peculiarity of this construction 

 may be observed when a horse lies down. The hock joints are 

 flexed to a certain extent, and then the animal falls down sud- 

 denly. He cannot, if he would, let himself down gradually, 

 and his rising from the ground is always with a sudden spring- 

 ing movement, or jerk. This peculiar mechanical contrivance 

 can be equally well observed in the dead subject, by dissecting 

 away everything but the lateral ligaments of the joint which 

 hold the articulatory surfaces of the joint in close apposition. 

 The joint movements being effected by the hands, they will be 

 found to move in one direction with a.jerk and snap movement. 

 The mere mechanism of the movement is therefore readily un- 

 derstood in this manner. From this mechanical peculiarity it 

 is deduced that the power or force that acts, as the natural 



