EXPERIMENTS ON NITRE. 71 
The small intestines were flushed through their whole length, 
but most in the duodenum. 
The caecum exhibited towards its apex two or three patches 
of a deep red colour ; though the large intestines generally were 
but slightly affected. 
The liver was scirrhous. 
The kidnies, ureters, and bladder, were in a healthy state. 
The lungs and heart were congested with blood: the left ven- 
tricle contained a considerable quantity of black coagulated 
blood, otherwise it was healthy. 
The following experiment was made fourteen years since, when 
the medicinal effect of nitre was the subject of much discussion ; 
but not having any minutes of the case, I shall not be able to 
describe it so accurately as it requires: — To a common sized 
hack-horse I gave two pounds of nitre in solution, about 11 o’clock, 
a.m. In the afternoon, a powerful diuretic effect commenced, 
which continued increasing until the following morning, when he 
shewed evident symptoms of pain in the kidnies, by stretching 
out his fore feet, and a cringing motion of the loins. These con- 
tinued until the evening, when they began to subside ; and after 
the third day nothing indicative of disease was observable. For 
some weeks afterwards this horse remained under my observa- 
tion, and in perfect health. 
My object in proportioning the doses of nitre (in Experiments 
IS os. 1 and 2) was, first, to observe its medicinal effect, and then, 
by continually increasing the quantity, to ascertain how much 
was necessary to destroy life. By giving it at 8 o’clock A.m., 
and at 3 o’clock, p.m., I had an opportunity of observing the 
operation of both doses during the day. In the first six days of 
Experiment No. 1, and when the horse had taken eighteen 
ounces, its effects are not deserving of comment :Vthe next three 
days, when he had taken forty-two ounces, his pulse only rose 
to 40 : the next day, the first of those on which he took two 
doses of eight ounces each, his pulse rose to 60 four hours after 
the first dose, and in seven hours after the second dose to 76 : 
the following morning they fell to 45, and did not again, during 
the three days, rise higher than 52 : the third day they were 50, 
and all unnatural appearances had nearly vanished. 
The action of the pound in solution, as of the other large 
doses, appeared to abate after about twelve hours : the diuretic 
effect did not increase in proportion to the quantity ; but, when 
continued in large doses, it seems to act in such manner as to 
produce retention of urine by constriction of the sphincter of the 
