the native population, has also exhibited itself by a tendency to diseases of the most malignant type. The fact plainly reveals itself, that exclusivism of diet, which may be borne in disease, as being essentially curative (In alimentum, pharmacum optimum,-Galen), is antagonistic to health, when established; and if studied in its influences upon communities, will often explain tendencies to physical degeneration, for which no other demonstrable cause exists. It is not sufficient to say that climate, or the national cereal, should alone determine the dietary of a people. For people differ everywhere individually, and each individual organism requires adjuncts to nutrition peculiar to itself.

Beginning with childhood, the law of food should be applied so as to meet

1st. The Wants of the Temperament.*

2d. The Wants of the Climate or Season. 3d. The Wants of the Taste.

In adult life questions of Occupation and of Taste may somewhat complicate this problem, but the order of its solution need not vary on that account. Temperament, first of all things, should be considered, for temperament is the portable climate of each individual, from whose influences he can never escape, in-door or out, summer or winter. He may incase himself in furs and escape the nipping air of the arctic zone; he may bury himself in bosky groves in the tropics, and so escape the parching

* Zeminormann: De l'Expérience en Médecine.

heat; he may dwell in any form of artificial atmosphere which he chooses to create; but with all these adjuncts he only modifies his external conditions. His temperament and its wants ever remain the same in quality, if not degree, and the balance of health can only be preserved by regulating his food accordingly.

SEPTICEMIC AND ZYMOTIC DISEASES.

But it is chiefly in that class of diseases ascribed now to a septicemic, and now to a zymotic origin, that the value of prophylaxis becomes incalculable. These diseases are often, at their inception, of difficult diagnosis. They are the offspring of causes wholly organic on one side, and only partially so upon another. In the most extreme form of their development, some pass beyond the boundary of a true disease, having cyclical periods, and obeying a law of definite duration, and exhibit the character of a cumulative poison, emphatic, swift, and destructive in action, from its earliest manifestation. In septicamic diseases, in particular, the early symptoms are variable, generally uncharacteristic of their specific nature, and resemble those of many varieties of febrile affections. Their true character is apt to be masked until the system is completely controlled by their disorganizing influences; and its curative reactions, when manifested, are too often incomplete and abortive. Hence their prognosis is usually uncertain, and as often unfavorable. They constitute the true opprobria of medical practice, yet, philosophically speak

ing, not more so than do any organic diseases when passed into their more advanced stages. Their successful treatment will depend, therefore, upon their early diagnosis, which becomes, in fact, the crucial point in the problem.

It may be said of them, at the outset, that, in common with all diseases involving changes in the constitution of the blood, their violence is in proportion to the period of their incubation;* for, whether we entirely accept the humoral pathology or not, we do not yet know of any agency in the human system which so directly and universally influences the balance between the organic functions, as the blood. It is true, doubtless, that the nerves have their appropriate part to play in regulating the harmony of functions-standing sentinel at points of exposure, or transmitting messages between contiguous or distant organs, so as to regulate their synchronous action. But before these regulators and messengers can act, there must be organs and functions on which to exercise their duties. In the genesis of the body the blood unquestionably takes precedence of all other constituent portions, and this priority in creation imparts to it a priority in influence which always renders it, not only the fons et origo, but also the primum mobile of life. A limb may be completely paralyzed, and though atrophied, will still live; but

* The death of our lamented Fellow, the late Professor D. S. Conant, of the University of Vermont, affords a striking illustration of the virulence of septicæmic influences, when permitted to act cumulatively, and thus thoroughly to saturate the system with their toxical qualities.

cut off the circulation from it completely, and it inevitably dies.

We must look unquestionably to the blood as the receptacle of septicæmic influences and zymotic germs, and the nidus for the specific reproduction of the latter. It is here that they are first received, imbibed, and commence their mission of development or disorganization. It is vain, therefore, to attempt to combat their influences locally, while the infected blood behind continues to pour a tainted stream throughout the body. All the world knows, for example, that the carbuncular or erysipelatous diathesis cannot be eliminated by poultices or external applications alone; but that, on the contrary, these means, whenever they do not prove abortive, are always found of subordinate importance and influence, as compared with internal remedies acting necessarily in and upon the blood, and without whose co-operation the former became only palliative and ephemeral. The vulgar saying, that in order to escape disease we must live above it, and that debility is an invitation to its attacks, is true physiologically; only, it fails to recognise the fact that debility, manifesting itself by a sense of persistent lassitude and general discomfort, is often the first stage of an existing disease, and the earliest note of warning given that the citadel of life is being undermined. Whenever such a condition is experienced without an immediate adequate cause, and wherever it continues to increase in the midst of repose or warmth, with headache superadded, and loss of appetite, it is justifiable to infer the presence of a disturbing cause in the blood. And if the sub

ject has been exposed to either septicemic or zymotic influences, we are authorized to consider them as the source of morbid disturbance. Certainly it is safer to do so in any event, for should the diagnosis be faulty, it will not diminish the chances of recovery from any less malignant diseases; and if it turns out that we are right, the probabilities of saving the patient's life, by antagonizing the disease at this stage of its existence, are increased an hundred-fold.

Fortunately for mankind, the sleepless science of chemistry, walking arm-in-arm with physiology and pathology, and lending her aid to both, has probed the storehouse of Nature, and evolved an agent competent, as hundreds of experiments have proved, to neutralize zymotic germs in the blood. This discovery, which bids fair to be ranked as the foremost of the century, is the result of the unfolding and reducing into scientific problems, of conjectures floating theoretically in the mind of every age, and transmitted as another seed-thought from past centuries to our own. From time immemorial, sulphur, to delov or Divine of the Greeks, as it was called, has been credited with the possession of detergent and prophylactic properties. As a purifying agent, it was largely employed in antiquity, and is frequently mentioned by Homer, Pliny, † and Dioscorides. Used in sacrifices and lustrations, it came to be universally known as a substance of inestimable value, and in every

*

* Odyssey, x. 481; Juvenal, Sat. 2, 157.

+ Pliny: Hist. Nat., 35, 50.

Dioscorides: lib. 5, 124; Moore's Hist. Anc. Metals, p. 48.