PHYSIOLOGICAL ACTION, AND ANTAGONISM. 
199 
twitchings occur. They appear first in the anterior extremities, and then spread 
all over the body to the hind limbs. This spasm increases in intensity, and often 
manifests itself by a number of clonic convulsions occurring at tolerably regular intervals. 
These seldom pass into a rigid tetanus. They are, however, provoked by touching 
the animal, by the application of cold to the surface of its body, or by a blow upon 
the table upon which it is resting. When the sciatic nerve was divided on one side 
before the injection of the poison, twitchings did not occur upon that side. The 
action of the salts of ammonia upon the circulation was also found to be various. 
Thus, in poisoning by the bromide, it was unusual to find the heart materially 
influenced in its activity, even when the most marked motor symptoms had been 
developed. With the iodide, however, an early arrest of the heart in diastole, with 
the auricles and ventricle distended by dark blood, was very usual. A larger dose of 
the phosphate, and not unfrequently an equal dose of the sulphate, had a somewhat 
similar effect. An examination of the blood showed that after poisoning by bromide 
of ammonium, a marked change had taken place in the red blood-corpuscles. These 
exhibited numerous coagulations in their stroma; an increase of free nuclei was like¬ 
wise observed in the blood ; where the blood from the corresponding limb to which 
the poison had not had access was examined, no such changes were observed. A 
similar result is occasionally noticed after poisoning by the sulphate ; it is much more 
unusual where the iodide and phosphate have been employed. 
Examination of the reaction of the muscle to direct and indirect stimulation was 
made as rapidly as possible, when it was desired to examine their reaction at any 
stage which the poisoning had reached. The ligatured limb was used for a contrast; 
and as it has been shown by Kuhne'“ that in cold-blooded animals the irritability of 
the muscle declines when containing blood in a condition of stasis, allowance must be 
made for this decrease in irritability when contrasting its reaction with that of the 
poisoned muscle. The irritability was tested by means of approximating the secondary 
coil of a DU Bois Reymond’s inductorium to the primary, the greatest distance at 
which a minimal contraction was produced being registered both for direct and indirect 
stimulation. This figure was controlled by removing the secondary coil from the primary, 
in which case contraction often persisted at a more distant position than it was observed 
at when the coil was approximated.t The muscle poisoned by bromide showed an in¬ 
crease of irritability in the early stages, and before the action of the poison was com¬ 
plete. There was a slight but less marked increase occasionally in the case of iodide, 
but usually the irritability in cases of slight poisoning is diminished. There is usually 
no marked increase of irritability in muscles poisoned by the phosphate and sulphate, 
though in exceptional cases it has been observed as a temporary condition in both 
The muscle responds to direct and indirect stimulation (opening shock) by a long, at 
first equally high, but then rapidly falling curve, in comparison with the normal. The 
* Archie, f. Anat. u. Physiol., 1859. 
t The excitability of the muscle appearing to be increased by its contraction. 
