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imperfect; yet if by auy effort this communication be again fully established, how wonderful often the result appears. If an old man's attention be roused to any important object,—if, by patient exertion, the desired impressions are fully conveyed to the mind, how often are we astonished by the clearness of comprehension, and the accuracy and power of judgment, in one who ordinarily may appear wholly incapable. When the external organs, more especially those of sight and hearing, remain unimpaired, the mind will be found active and vigorous up to the latest period of life; it is only where these have become impaired, that the mind appears to partake of the corporeal decay. There is often in old people a remarkable loss of memory, especially of the names of persons or things, and of events of recent occurrence; whilst events which occurred many years before, even in early life, are minutely remembered, and the names of the actors correctly retained; but in all probability the impressions made on the mind in early age, when all the organs possessed greater power and activity, were much more deep, and therefore more durable; that the impressions made in old age are more slight, and hence more evanescent; again, probably the events of early life had been often in the course of past years recalled by memory; that is, the original impressions had been, as it were, strengthened by repetition. Again, I think it will be found in such persons that memory is not the only faculty of the mind that appears to be failing; the perception will also have become less acute; the imagination less vivid, but these facts are seldom noticed by the old man. "My mind is gradually getting weaker," he will say; "I cannot remember things as I used to do— I forget even what happened yesterday;" but he does not observe, or at least does not complain, that the play of his imagination has ceased; that the days of poetical fancy have gone by; that he no longer perceives things by means of the external senses, with the clearness and readiness of former times. Why, then, should he expect the memory to retain its former power? nay more, why should he expect it to recall the weak impressions of age with the same facility as the powerful perceptions and vivid imaginings of early life? Whether we believe the brain to act as a whole, or in distinct portions, it is easy to understand that as it becomes altered by age (indurated), the mental faculties dependent on its actions will become more obtuse; whilst the judgment, the great reasoning faculty of the mind, being wholly independent of matter, remains unimpaired.
The power of procreation ceases early in women; often, indeed, long before the period of age. In men, it continues to an indefinite period, becoming gradually less and less. The urgency of desire and the power of exertion gradually diminish, until at length they cease altogether; and the genital organs, being no longer required, shrink considerably in size; the testicles become soft and pulpy, and sometimes almost disappear. In women, the ovaria shrink, the mamma? become soft, pendulous, and diminished in size; and the uterus shrinks into a very small volume.
The circulation of the blood continues with but little change until the end of life. The heart becomes weaker and slower in its action, but goes on regularly, driving the blood to, and receiving it again from, all parts of the system. The pulse is slower, and the wave of blood feels more equable under the finger; there is less sensation of tonicity in the arterial tubes, as if they exerted less influence in the circulation of the blood, and were more passive than formerly; sometimes there is a harshness in the feel of their coats, but this I regard as a diseased condition.
There are many causes which impair the digestive powers in old age; the chief of these is the loss of teeth, which decay or become loose, and drop out: hence the jaws approximate to each other, and the chin projects; the toothless gums are unable to tear the food, which therefore passes into the stomach without the very important preparation which it should receive by full mastication; yet, even in advanced age, the digestive functions go on tolerably well.
Even as the circulation of the blood continues to keep up the vitality of the body, so the nutritive organs continue to supply to the blood fresh matter, and the bowels, kidneys, and skin, to eliminate the refuse. The absorbents carry off portions of the former, which the secretory organs renovate; and, as long as these reciprocal actions of organic life go on, the individual continues to live a passive and inactive state of existence, the duration of which is wholly uncertain. The slightest impediment may readily stop the whole:—
"Erom nature's chain whatever link you strike,
But, unless something does occur to interfere with this regularity, it is really impossible to say how long this train of actions, dependent on each other, may continue; or, in other words, no one can say how long a man can live, so long as food continues to be supplied and digested. Organic life goes on, and this with but little reference to its twin brother, animal life, which may be suspended or may have almost ceased. In this state of extreme decrepitude, the individual may seem
to be unconscious of external impressions, scarcely capable of thought, speech, or action, and yet live on for some time. Even as it occurs at all ages during sleep, that although the animal and mental powers are quiescent, and, indeed, appear to be for the time dead, yet that life is sustained by the organic system alone : so in extreme old age, although the animal powers are almost lost, and the mental powers are incapable of giving any manifestation of existence, yet the individual lives a kind of vegetable life, until some accidental occurrence or derangement breaks the chain of digestion and circulation, and thus closes the scene.