58G STRING-HALT-ITS DOUBTFUL TATIIOLOGY. 
bay horsOj with very bad string-halt in off hind leg; his limbs 
plainly told the hard w'ork he had undergone; he had liog 
spavin in the nigh and thorough pins in both hocks. Had 
him destroyed with cyanide of potash. Tlie brain^ the spinal 
marrow^ the nerves and their membranes, were carefully ex¬ 
amined, as also the muscles and their tendons. The crural 
nerve was followed through its entire course, but not the 
slightest trace of disease could I discover. My attention was 
now directed to the hock-joints, beginning with the off one, 
on opening which I found the capsular ligament much thick¬ 
ened ; a large quantity of synovial fluid, and ulceration of the 
astragalus in the groove between the trochleae—the articular 
surface of the large cuneiform bone, on its superior face, was 
also ulcerated. I next examined the nigh hock; the capsular 
ligament was like the other, much thickened, and contained 
a much larger amount of synovia; the joint, in other respects, 
appeared normal. 
Case 2. — A patient, whose child I was attending, asked me 
to look at the foot of his horse, which had been run over by 
a cart in the early part of the morning, remarking at the time 
that he would not take §500 for him, although he had string- 
halt in both legs—a fact known to me, having often seen him 
travel. After examining him, I advised his destruction, the 
hoof being crushed and the bones within fractured. He was 
bled to death, after which I had him removed to a shed in 
my stable yard, for the purpose of making a post-mortem. I 
commenced by opening the skull and vertebral canal, expos¬ 
ing the brain and spinal marrow, following the nerves from 
the sacrum to the hoofs, but failed in detecting any indication 
of disease. I next removed the nerves, commencing at the 
hoofs; also all branches, including the crural, which I had 
previously traced into the muscles, with the spinal marrow 
and brain. I laid the whole on a board, and examined Avith 
care the coverings of the brain and medulla spinalis, Avithout 
detecting disease; the substance of the brain and marroAv 
Avere both healthy. There was no anchylosis of the vertebra). 
On examining the hocks, there Avas no external sign of disease. 
I opened the oft‘ hock, and found an ulcer in the groove of 
the astragalus, extending from a little beloAV its middle up- 
Avards; between the trochlere there Avas also ulceration at 
the inferior point of the articular ridge, lying betAveen the 
malleoli of the tibia; the cuneiform and cuboid bones were 
firmly anchylosed. The astragalus of the nigh hock aa rs 
likeAvise ulcerated in the same place, but not to the same 
extent; the other bones of the joint Avere free from disease. 
