The organs of respiration consist of an external serous and an internal mucous membrane, united together by cellular tissue. Each of these is the seat of a peculiar inflammation (pleurisy, pneumonia, and bronchitis), attended by different symptoms and requiring a variation in treatment. There is likewise, as in all other inflammations, an acute and a chronic kind, so that here we have six different inflammatory disorders of the organs of the chest, besides heart disease and phthisis or consumption. All the acute forms are attended with severe sympathetic fever, and quick pulse; but the character of the latter varies a good deal. The chronic forms have also some slight febrile symptoms; but generally in proportion to the acuteness is the amount of this attendant or sympathetic fever. As these three forms are liable to be easily mistaken for each other, I place the symptoms of each in juxtapo-sition in the following Table:

Comparative Table Of Symptoms

Acute Pleurisy.

Acute Pneumonia.

Acute Bronchitis.

Early symptoms.

Shivering, with alight spasms of the muscles of the chest; inspiration short and unequal in its depth, expiration full, air expired not hotter than usual; cough slight and dry; pulse quick, small, and wiry.

Strong shivering, but no spasms; inspiration to erably full, expiration short, air expired perceptibly hotter than natural; nostrils red inside; cough violent and sonorous, with expectoration of rusty colored mucus; pulse quick, full, and soft.

Shivering, soon followed by continual hard cough; inspiration and expiration equally full; air expired warm, but not so hot as in pneumonia; cough soon becomes moist, the mucus expectorated being frothy, scanty at firs':, but afterwards profuse; pulse full and hard.

Stethoecoplc

Bounds.

No very readily distinguishable sound. A practised ear discovers a friction sound or rubbing.

A crackling sound, audible in the early stage, followed by crepitating wheezing.

The sound in this form varies from that of soap bubbles to a hissing or wheezing sound.

Percussion.

Produces at first no result different from a state of health. After a time, when serum is thrown out, there is increased dullness.

Dullness after the early stage is produced by the thickening of the tissue, approaching to the substance of liver, hence called "hepatization."

No change.

Termination.

The symptoms either gradually disappear, or lymph is thrown out, or there is an effusion of serum or matter, with a frequently fatal result.

If the symptoms do not disappear, there is a solidification of the lung, by which it is rendered impervious to air, ana in bad cases suffocation takes place, or matter is formed, producing abscess.

The inflammation generally subsides by a discharge of mucus, which relieves the inflammation: or it may go on to the extent of causing suffocation by the swelling of the lining membrane filling up the area of the tubes.

Treatment.

Bleeding in the early stages, in degree according to the severity of the attack. Relieve the bowels by (12) or (13). No blistering, which is actually prejudicial. Try the fever powder (49) or (50), and if not active enough, give calomel and opium, of each 1 grain, in a pill, 3 times a day. Low diet of slops only.

Bleeding in the early stages, in amount according to the severity of the attack. Give an aperient, (12) or (13). Blisters to the chest of service, or the mustard embroca-tion (42). Give the cough bolus (46) or the draught (47 . If the inflammation is very high, give calomel and opium, of each 1 grain, digitalis, 1/2 gmin, tartar emotic, 1/4 grain, in a pill, 3 times daily. Low diet of slops.

No bleeding is required. In the early stage give an emetic (44). Follow this up with a mild aperient, (11) or (15). Apply the embrocation (42; to the chest, and give the cough bolus (46) or the draught (47). Low diet in the early stages; afterwards, a little solid food, not meat, may be given.

Comparative Table Of Chronic Symptoms

Chronic Pleurisy.

Chronic Pneumonia.

Chronic Bronchitis.

Early symptoms.

Inspiration slower than expiration; cough dry; pulse quicker than natural, small and wiry.

Respiration quick and painful; cough troublesome but restrained: expectoration trifling: pulse quick and full.

Respiration quick but free; cough constant and severe, but without pain; pulse scarcely affected.

Termination.

Either in a cure, or else there is an effusion of serum into the chest, and generally also into the belly and limbs, causing suffocation by pressure.

If not ending in a cure, there is great difficulty of breath-ing, often ending in suffocation. The animal does not lie down, but sits up on his hind legs, supporting himself on his fore legs.

Ends in a cure, or in a permanently chronic state of inflammation. Or, if fatal, there is suffocation from effusion, but this is very rare in chronic bronchitis.

Treatment.

The same as for acute pleurisy, but milder in degree, i and the diet is not • required to be so strictly confined to slops.

Bleeding will seldom be required. Give the calomel,; opium, and tartar emetic, without the ' digitalis, in the doses ordered for acute pneumonia. After a few days, have recourse to the bolus (46). Diet nourishing, but strictly confined to farinaceous articles. The embrocation is of great service.

Dispense with the emetic, and at once try the cough bolus (46). In very mild cases, give ipecacuanha 1/2 grain, rhubarb 2 grains, opium 1/2 grain, in a pill, 3 times a day. Apply the mustard embrocation (43). Milk diet, with nourishing slops.

These various forms constantly run into one another, so that wo rarely find pleurisy without some degree of pneumonia, or pneu-monia without bronchitis. Still, one generally predominates over the other, and, as far as treatment is concerned, the malady predominating may be considered as distinct. So, also, there is every shade between the very acute form, the acute, the subacute, the chronic, and the permanently chronic. For practical purposes, however, the two divisions are sufficient.