689 
STUDY OF SPINAL CORD OF SPRING-HALT HORSE. 
the time of its destruction it was practically worthless. The 
attention of Dr. L. H. Howard, President of the Massachu¬ 
setts Veterinary Association, was called to the animal in the 
summer of 1889. He gives this description of its symptoms 
and efforts at locomotion at this time: “ The animal, on being 
moved, would pick up each hind leg with a quick, jerky mo¬ 
tion, characteristic of spring-halt, but the great excess of 
motion seemed to be that of abduction; the whole limb would 
fly out away from the body, so much so that he would some¬ 
times hit it against the shafts of the vehicle to which he was 
harnessed. The foot came back to the ground, however, in 
proper advance of the point of leaving it, and progression 
was accomplished after the animal was once in motion. The 
muscular contractions quickly diminished until they became 
nearly normal, and did not take place again while he was trot¬ 
ting. On dropping his gait to a walk, they would sometimes 
occur again for a few steps ; when he had come to a standstill, 
then always on starting again the above-described movements 
would take place. These symptoms all the time increased 
until the animal came into our possession in the summer of 
1891. He had then become an exaggerated case. The mo¬ 
tion of abduction was now so excessive that he would throw 
the first limb lifted so high that he would lose his balance, 
and be obliged to hop on the opposite limb, when that in turn 
would fly out and up so high that over he would balance on 
the first one again, and thus he would ‘dance the ballet’ for 
several seconds before being able to progress at all. Finally 
the excessive contractions would subside enough so he could 
step forward, and he would trot off all right for a longer or 
shorter distance, when he would have to stop and again have 
his ‘dance.’ In some instances the throwing up of the limb 
would so overbalance him that he would fall to the ground. 
If moved suddenly in a stall of ordinary width, he would 
strike first one side of it and then the other several times with 
his hoofs.” In June of 1891 the animal was placed in charge 
of Dr. Howard for experiment. He invited several, veterin¬ 
ary specialists, who were interested in spring-halt, and who 
had theories of the nature of the disorder, to try their treat- 
