TO PROVE BY DEMONSTRATION THE TRUTH OF THE PROPOSITION NOW PROPOUNDED, IT IS NECESSARY TO GIVE EXAMPLES OF CASES WHICH OCCASIONALLY PRESENT THEMSELVES:

First Example.

A man who receives a smart blow on the semilunar ganglion, or the superior cervical ganglion, will fall to the ground; animation will be for some time suspended, in consequence of the shock given to the ganglion being communicated to the pulmonary ganglion, as well as all the other ganglions, incapacitating the pulmonary organic glands to evolve electricity or vital fluid to unite the oxygen of the air with the venous blood.

Second Example.

A delicate lady sometimes, on smelling a sweet-scented rose, will faint; animation will be suspended for a longer or shorter period. The vapor emitted from the rose passes with the air into the lungs, and on coming in contact with the pulmonary glands destroys their power of giving off electricity or vital fluid to unite the oxygen of the air with the venous blood; hence suspended animation or fainting ensues, in consequence of the want of oxygen to unite with the organic glands.

Third Example.

A man falls from a height; he is taken up, apparently lifeless; his countenance is ghastly pale; his respiration is imperceptible; his pulse ceases to beat; his surface rapidly becomes cold; besides, he may have involuntary discharges. The shock is communicated to the entire organic nervous system; the pulmonary glands are unable to give off electricity

systems, and the same quantity of carbonic acid is formed as under ordinary circumstances, no heat is generated, and (in consequence of the cold air thrown into the lungs) the animal cools more rapidly than one that is actually dead."Phil. Trans., 1811.

The shock the organic nervous system receives, when preparing to institute the experiment, as performed by Sir B., accounts for the loss of temperature, as will be explained more fully elsewhere. That PITHED or DECAPITATED ANIMALS must sustain a tremendous shock, requires no arguments to prove.

or vital fluid to unite the oxygen of the air with the venous blood, in its passage through the glands: hence the suspension of life, for the want of oxygen to unite with the organic glands; respiration, therefore, as just stated, is imperceptible. The absence of the pulse is attributable to the loss of nervous power, produced by the shock; the coldness of the surface, or loss of animal heat, is caused by the want of oxygen to unite with the organic glands all over the body.

Fourth Example.

When a person has been immersed in water for some minutes, (three or four,) he will appear lifeless; all the operations of life will be suspended; yet life will still continue to occupy the organic nervous system, and may have its operations restored by proper treatment. The pulmonary glands, although for a moment they may be able to evolve electricity or vital fluid, yet have their functions quickly rendered powerless, and in a short time the operations of life cease all over the body, for the want of oxygen to unite with the organic glands.

Fifth Example.

When a man goes down into a deep well, that has been closed for some time, and which is full of carbonic gas at the bottom; or enters a tomb that has been recently opened, and is filled with sulphureted hydrogen, he is observed to fall suddenly. The instant the gases in question come in contact with the arytenoid muscles, spasm or closure of the glottis is the result: no air can enter into the lungs, consequently no oxygen can be supplied to the blood; and death necessarily follows, for the want of oxygen to unite with the organic glands.

The terms applied to the causes of death just mentioned, (in 4th and 5th examples,) in my opinion, are not philosophical, viz.: apnœa, (å, priv., пvɛw, spiro;) and asphyxia, (å, priv., σφυξη, pulsus.)

Sixth Example.

When a large quantity of blood flows from the body, fainting or suspended animation is the result. In such a case, the

countenance becomes pale; the surface cold; the person tosses about, and gasps for air. The pulmonary glands are making strong efforts to sustain life, but are baffled in their attempts to do so, in consequence of the deficiency of the supply of blood to convey the oxygen to the organic glands: hence fainting or suspended animation is the result, caused by the want of oxygen to unite with the organic glands.

When all the blood is drained off, death is the result, in consequence of there being no blood to carry the oxygen to the organic nervous glands.

Seventh Example.

When a hare is run to death, the blood is found liquid and dark-colored. The organic nervous system has become completely exhausted; the pulmonary glands are unable to give off electricity or vital fluid to unite the oxygen with the venous blood: death is caused, therefore, by the want of oxygen to unite with the organic glands. (The appearance of the blood proves this statement to be true.)

Eighth Example.

When an angler has got a large trout on his hook, he gives him the full length of the line, allowing him to dart through the water freely, until ultimately, the fish, when completely exhausted, floats on the surface, and is easily captured. Here the organic nervous system has become so exhausted that the gills are no longer able to evolve electricity to unite the oxygen of the air contained in the water with the venous blood, and the fish loses the power of resistance.

Ninth Example.

HUMBOLDT's description of the manner in which the South American Indians capture the Gymnoti is worthy of consideration in connection with this subject. A number of wild horses are driven into a pond in which the fishes inhabit. The fishes become excited by the presence of the horses; they make a furious attack on them; they give repeated shocks to the bellies of the horses, but they soon become exhausted, and float,

almost lifeless, to the margin of the pool, when they are casily captured. The organic nervous system of the torpedo becomes exhausted on the same principle as the organic nervous system of the hare and the trout.

Certain agents increase the quantity of oxygen in the blood; others diminish it, by their action on the organic nervous system; whilst an operation may destroy its existence altogether. A familiar example of the effect produced by the first agent is daily presented, viz.:

First Example-"Increase of Oxygen in the Blood."

A man drinks two tumblers of warm punch immediately after dinner; the punch stimulates and invigorates the organic nerves distributed on the internal surface of the stomach; the stimulation and invigoration are propagated to the whole organic nervous system; in addition, it may be stated, some of the punch is absorbed, passes by the thoracic duct into the venous circulation, stimulates the pulmonary glands in its passage through the lungs, as well as stimulates the organic glands on the union of the oxygen with the latter. Hence the glow of heat that pervades all the body; the flushed and animated countenance; the quickened respiration and great vascular excitement. To understand how all these matters have been brought about, it is necessary to recollect that the vital powers of the organic nervous system have been augmented by the action of the brandy; that the power of the organic pulmonary glands to give off electricity or vital fluid has been increased; that consequently a greater supply of oxygen is supplied to the blood, so that the quantity of oxygen being increased, the temperature of the surface of the body is elevated.

Second Example-" Decrease of Oxygen in the Blood." Another man eats some tobacco; the tobacco depresses, nauseates, and exhausts the organic nerves of the stomach. The depression, nausea, and exhaustion are communicated to the organic nervous system; the man gets deadly sick; his muscular power rapidly diminishes; his heart pulsates weakly; his respiration grows feeble; his surface gets cold. To explain

these symptoms, it is only necessary to remember that the effect of the tobacco on the organic nerves of the stomach extends to the whole organic nervous system, inasmuch as the whole organic nervous system is connected together; that the pulmonary organic glands, under such circumstances, are unable to evolve electricity or vital fluid to unite the oxygen with the venous blood; that consequently coldness of the surface must ensue, the quantity of oxygen in the blood being diminished; the feeble action of the heart and arteries is caused by the loss of vital power in the cardiac nerves, and the retina of nerves distributed to the coats of the arteries; the feeble respiration and tendency to faint are caused by the pulmonary glands being rendered incompetent to discharge their functions.

Third Example-" Cessation of Oxygen in the Blood."

When the external iliac or femoral artery is tied for aneurism, mortification is to be apprehended. The circulation of the blood being impeded, the supply of oxygen is cut off; the union, therefore, between the organic glands and the oxygen ceases; the provision for creating animal heat, by the union of the oxygen and organic glands, is suspended; coldness of the part is the result. The vital spark being extinguished for the want of oxygen, death takes place. The explanation of the causes which produce mortification of an extremity, where the circulation has been arrested, is now explained.