158 VETERINARY MEDICAL SOCIETY. 
ranked among the narcotics, and had its primary and chief action 
on the brain. Its action on the heart was but secondary, and 
often weak, compared with that on the sensorian. Digitalis had 
a more immediate effect on the heart. It speedily lowered the 
circulation, without oppression or coma. It produced a singular 
intermittent state of the pulse. It likewise possessed some diu¬ 
retic power, and no bad consequence had ever been known to 
result from its exhibition. 
Mr. Field acknowledged the power of digitalis on the circu¬ 
lation. He had seen the pulse lowered by it from 84 to 42; but 
as to the effect of hellebore on the brain, he thought Mr. Youatt 
followed too much the theory of human surgeons. He had seen 
no bad effects from hellebore in the doses in which he gave it; 
and the intermittent pulse might be produced by other causes, 
and was often found where no medicine had been given. 
In answer to another question, he gave thesp. seth. nit. in doses 
of one or two ounces, and especially where rigors, and oppressed and 
indistinct pulse occurred. He usually found that the natural 
warmth of the surface returned, that the pulse was brought out, 
and ^although there was no apparent sweating, the insensible 
perspiration was restored. 
He gave nitre as a refrigerant in cases which did not indicate 
the use of the nitrous sether. Of the effect of the tartarized anti¬ 
mony he was somewhat uncertain; but he was inclined to con¬ 
sider it as a relaxant and diaphoretic. 
The operation of paracentesis was then considered. Mr. Field 
thought that when effusion commenced the first symptoms of 
pleuritic inflammation began to subside; viz. limited respiration, 
spasmodic affection, and hardness of pulse ; the inspiration was 
prolonged, and the respiratory murmur began to cease. It was, 
perhaps, impossible to detect the very commencement of effusion, 
but the attentive surgeon would soon recognise it, and easily dis¬ 
tinguish it from symptoms of healthy resolution. We were not 
warranted to operate until the process of respiration was materially 
affected, and the animal was evidently oppressed. He regarded 
the effusion as a remedial effort of nature ; but so much debility 
had often taken place, that the absorbent vessels could not follow 
up this action. 
Mr. Youatt thought that if the operation of paracentesis were 
attempted at all, it should be in the very earliest period of effusion, 
before the habit had been established, or the lungs too much de¬ 
bilitated by laborious action against the pressure of the water, 
and their substance condensed, and their bulk diminished, by 
that pressure. 
