70 ON WOUNDS PENETRATING INTO THE CHEST. 
is, that the fibrous coagula, small in bulk, have a loose and open 
texture, and, if they are not attached to the pleura, float in the 
effused fluid. 
13. Simple Wounds in the Walls of the Chest, with the Injection 
of a saline Soliiiion. 
We have experimented only with the solutions of the tartrate 
and nitrate of potash, in the proportion of two drachms of the 
salt to five decilitres (a little more than a pint of water), and at 
a temperature of 54'^ Fah. 
We remarked in two cases, that, as soon as the solution was 
injected, the animal had a shivering fit, and that he gathered 
his legs under him and lay down. The respiration and the pulse 
were much accelerated ; they again became slower when ten mi¬ 
nutes had passed, but did not regain their natural standard. 
Then succeeded all the recognized symptoms of pleurisy and 
pneun:ionia. 
On one of the horses, into w'hose chest we had injected a so¬ 
lution of nitrate of potash, we attempted a double experiment, 
with the view of discovering what might be the influence of in¬ 
tense pleurisy on the absorption of blood injected into the chest. 
The injection of the saline solution was made on October 27th. 
On the 30th, the horse, although he had pleurisy well marked, 
was yet tolerably lively. We therefore attempted to inject four 
pounds of blood into his chest, by means of the opening through 
which the solution had passed ; but we found an obstacle to this 
in the thickness of the walls of the thorax, for false membranes, 
of considerable firmness, had already closed the aperture. As, 
for aught that we knew, the lung might be here adherent to the 
side, we preferred to make a new opening more posteriorly, 
where we should run less risk of finding false membranes. We 
were thus able to inject the blood immediately after it had been 
drawn from the jugular. This new experiment hastened the 
death of the horse. He died on the 31st, at night. 
He, like most of those on which we had experimented, had 
retained his appetite almost to the last. This would prove that 
there is a difference between pleurisy arising from the ordinary 
causes of that disease, and produced by the introduction of a fo¬ 
reign body into the pectoral cavity. This difference is in general 
very manifest, not only by the preservation of the appetite, but 
by other symptoms, which every experienced observer will easily 
recollect. We know, besides, that nothing is so difficult as to 
reproduce artificially a disease which has come on spontaneously; 
therefore it is that experiments of this kind, although useful, 
will never accurately discover to us the nature of the different 
lesions which either constitute the disease, or are produced by 
