This is a condition of the organism characterized by loss of vitality, or deterioration and diminution in the quality and tone of the vital forces. It is one of the chief predisposing causes of disease, and is of itself a condition characterized by all the elements of ill health. The principal causes of debility are improper nourishment, impure air, excessive bodily and mental exercise, want of exercise, long exposure to intense heat or cold, intemperance, depressing states of the mind, and of course a prostrative disease. When not a heritage of the organism, it is generally produced by some flagrant violation of physiological law, depleting the vital forces by the disorganization of organic functions which ensues, or by the loss of vital elements through the eliminating organs, chiefly the kidneys.

That the reader may have a correct understanding of what is meant by vitality, it may be well to give its physiological sense. Though derived from the Latin vita, life, it has a somewhat different signification from that which is expressed by the word life. It signifies the constituent principle or essence of life rather than the entity itself. Hence vitality is not properly life, but the element conducive to its perfection and prolongation. It is that principle that gives to the physical organization its vigor, elasticity, and tone, to the mental organs, acuteness, vivacity and sprightliness, and to the whole organism a high standard of health.

If the habits are not in violation of hygiene or physiology, and the expenditure of the vital forces not exceeding the production, the normal condition of the organism would be one of health and vigor, and almost complete immunity from disease. If the expenditure exceeds the production it engenders the condition termed debility. Improper and sinful habits of life, especially in the young, are alarmingly destructive of vitality in consequence of engendering diseases characterized by losses of vital secretions. The intemperate very frequently incur the penalty of over-indulgence in intoxicating beverages by inducing structural diseases of the internal organs, especially Bright's disease of the kidney, wherein the blood becomes devitalized by loss of its albumen through the urine. In the male economy at an age often quite immature there is induced an affection characterized by involuntary expenditure of a secretion, directly by an improper and sinful life. The element thus constantly expended, and which occurs invariably without any exercise of the voluntary powers, is beyond all question the most highly organized and more intrinsically vital than any other secretion of the organism. This affection, peculiarly masculine, is one of the most prolific causes of debility and is conducive to greater physical misfortune than any other pathological condition induced by violation of physiological laws. The chemical nature of the secretion is highly phosphatic, and as phosphorus is a very important constituent of nerve tissue, its constant involuntary escape from the organism, whether in the urine or otherwise, preys fearfully upon the nerve tissue for phosphatic supply, and eventually, and often quite rapidly, produces atony of the nerve-centres, and a general intonicity of the nervous system, or what is more commonly known as nervous debility. Of the various systems composing the organism the nervous can least afford to lose its vitality, or to become enfeebled. It is the principal or controlling system of the organism, the others being more or less subordinate. If by any depleting causes its just complement of the vital forcs becomes reduced, its individual integrity is not alone compromised or destroyed, but muscular action, circulation, digestion, assimilation, and the mental operations also become enfeebled, hence the vital standard of the nervous system is of extreme importance to the general welfare of the whole organism.

Precisely the same pathological condition results from another cause, a sedentary habit of life. It is due to such exciting causes that clergymen and other persons of sedentary habits suffer so frequently from nervous or general debility. When the muscular system is permitted to degenerate from want of proper exercise it gives to the organism a condition of laxity or intonicity which in the male induces the previously mentioned loss of a highly vitalized secretion, and in the female an uncompensated loss of nervo-electric force. Debility is the result in both cases, though the devitalization is more rapid in the male, proportionally to the physical vigor inherent to the different sexes, than in the female. This is explained by the fact that in the male economy a greater loss of the phosphates occurs. In all persons of studious habits, and where bodily exercise is insufficient, the urine is loaded with phosphates, which is indicative of the breaking down of nerve tissue. Consequently in the male there is not only the usual phosphoric loss due to nervous waste, but the super-addition of the involuntary loss of a secretion which, as has been stated, is highly phosphatic in its chemical nature, makes the depletion of the phosporus essential to a vital condition of the organism, doubly great.

In a debilitated condition of the nervous system, or, as it is usually denominated, nervous debility, from whatever cause the loss of vitality may ensue, there is in general quite a train of symptoms, as may be supposed when this more important part of the economy has become devitalized. This form of debility may usually be recognized by a marked facial expression, a characteristic mannerism, and by a peculiar mental state. The skin of the face is pale and sallow, and usually affected with acne; there is a dark circle around the orbits, the pupils are dilated and sluggish, the eyes become lustreless, and the face has a haggard, troubled furtive expression. These physiognomic characteristics are due to atony or want of tone in the cerebral nerve-centres, and from the same cause the devitalized patient is listless, shy, retiring and easily confused, society loses its charms, and solitude is preferred, but has, however, no compensating or satisfying influence over the patient. There is a want of steadiness and decision in his locomotion, his inferior extremities are deficient in power, and all the movements are suggestive of a mind ill at ease. The mental operations are confused, speech becomes awkward and often without directness; memory is defective, and the patient is usually absent-minded and given to reverie. Pains in the lumbar region, and a sense of weight and aching in the loins are experienced. The appetite is capricious, and digestion feeble. The mind is deficient in power of attention, the imagination is constantly pervaded with vague erotic dreams, the moral sense is blunted and the perceptions are dull and confused. Pains in the coursse of the principal nerves and extreme nervous sensibility are experienced. The patient also can fix his mind on any subject with difficulty; his attention wanders, and he is given to day-dreams and erotic visions.  The urine, of course, contains phosphates, the source of which, whether nervous or secretional, is easily determined by analyzation or microscopical examination. Urates are also found in the urine. Those who suspect such vital loss, may with sufficient certainty for all practical purposes ascertain the fact by a simple experiment. The morning urine should be placed in a clean half-pint bottle, and let it stand from forty-eight to seventy-two hours. If there is then found a remarkably peculiar or cloudy sediment or deposit at the bottom, the fact is quite evident that some of the losses alluded to occur, and proper aid should be sought at once.

Such, briefly, are the evidences of a devitalized nervous system. The condition, as is palpable to every one, is fraught with danger to the general welfare, and even to life, if the process of depletion of the vital forces continues too long, or, if, by special virulence of the exciting cause, the devitalization is rapid in occurrence. Any loss of vital power should be regarded with solicitude and deep concern by every one who places a proper estimation upon vigor of the organism and its special functions. Careful and judicious treatment must not be neglected, as by such a course only can revitalization be speedily and adequately effected. As soon as loss of vital force becomes apparent, so soon should the services of a competent and experienced physician be engaged. In any stage of devitalization, rehabilitation of the organism with vitality can again be accomplished, the only requirement being employment of competent medical aid, and the exhibition of viralizing remedies. Revitalization can, however, only be effected by herbal remedies, as their organic nature alone afford the elements required for reendowment of the system with vital force. Minerals are lifeless, and can there impart no vital element.

Those desiring to consult the author with reference to debility or loss of vitality from any cause whatever, may refer to page 385, where his mode of treatment is described, and to page 390, where the necessary questions are asked.