264 LIVERPOOL VETERINARY MEDICAL ASSOCIATION. 
year 1842, and subsequently by that great and noble professor, the late 
Professor Dick, with very great force and emphasis, that two acute 
inflammations could not exist at the same time in a living animal, and 
by producing an external artificial inflammation you must of necessity 
relieve the internal morbid one. Reasoning and clinical observation in 
the sick box have materially modified this opinion. When counter- 
irritants operate so mildly as merely to excite the capillaries without 
occasioning any effusion of serum, they are called rubefacients; but if 
by increased strength or continued application they excite the vessels 
into such a state of inflammation as to terminate in effusion of a serous 
fluid, and the elevation of the papillse of the skin forming what are 
called vesicles, which gradually enlarge, and by their lateral extension 
soon coalesce, so that blebs of different size are produced, they are 
called vesicants. These vesicles are filled with a fluid rich in albumen, 
and generally contain some fibrine. Or when a still higher grade of in¬ 
flammatory action is produced, as by the application of tartar emetic 
ointment, they are designated suppurants. 
In acute inflammation of the organs of the chest the counter-irritant 
I chiefly rely on or apply is the best mustard mixed with tepid water, 
in other words, a mustard cataplasm ; when applied to the walls of 
the chest and breast it produces in a little time a sensation of pain, heat, 
redness, and swelling, the immediate effect as upon the peripheral ex¬ 
tremities of the nervous system, and through them to the nervous 
centres, and from the nervous centres we have a reflex motor action, 
thereby increasing the action of the capillaries and the circulatory 
system on the surface upon which the counter-irritant is applied. If 
counter-irritation abstracts a large amount of nervous force and causes 
a great determination of blood to the part upon which it is applied, 
combined, secondly, with large effusions of serum within the areolar 
tissue, we must, I think, without the slightest doubt, relieve the vital 
organ or organs affected with morbid action ; and that we do so we 
know by careful observation of our suffering patients; we see the acute 
pain modified or relieved, and the cough reduced; the pulse becomes 
more soft and lower, the breathing more tranquil, the temperature 
lessens gradually, and the secretions and excretions become more 
regular and natural. In fact, gentlemen, the countenance and the 
healthy condition is resuming its normal and wonted standard, a con¬ 
dition which any of us always welcome and are delighted to see in our 
suffering patients. In pleurisy, pneumonia, or pleuro-j?neumonia, the 
mustard cataplasm should be applied over the walls of the thorax, 
throat, and breast; the greater extent of surface of the skin to which 
the mustard is applied the greater will be its influence on the in¬ 
flammatory action of the organs within. 
Thirdly, if it acts as before mentioned, when and how should it be 
applied? Well, to practically qualify this, I will relate a supposed case. 
A very expensive cart-horse, recently purchased, rising five years of age, 
has changed hands, thereby changed diet, stables, and his daily work 
and climate. He has, during the last week, improved very much in his 
condition. He is suddenly seized, after dinner-time, or in the evening, 
with a rigor or shivering fit; pulse hard and quick; breathing quickened ; 
temperature 104°; faeces coated with mucus; Schneiderian and conjunc¬ 
tival membrane increased in redness. Auscultation may detect, accord¬ 
ing to the degree, whether the pleura or parenchyma is mostly affected. 
The friction sound in pleurisy—a rustling or laboured action if it is 
pneumonia. If my patient is admitted when the rigor is set in, my first 
duty, after a careful examination, is to administer a nerve stimulant, 
