chosen as a seat for colonies of young tumor cells, and the socalled metastatic tumors; after this all of the organs of the body, noticeably, the spleen, liver, bones and connective-tissue.

The process thus described is the typical plan of attack pursued by malignant tumors in their rude invasion of the organism. The involvement of the neighboring lymph glands, and the appearance of metastatic tumors, betokens the malignity of the tumor, and is a valuable guide in the diagnosis.

A much more dangerous and important invasion, which begins earlier and which is of greater continuity and intensity than that made upon the cells, is the admixture of the liquid products of metamorphosis which form in the tumor and are absorbed by the lymphatics. Although little is known of the chemical properties and other characteristics of these products, we may be sure that they are actively employed in undermining the entire nutritive apparatus of the patient. They are, probably, fermentative substances which act upon the albumen of the blood in the same manner as the gastric juice, dissolving it and impeding its reproduction. For the most prominent symptom of that blood cachexia, which is certain to result fatally, is the increasing impoverishment of the blood, in respect to its free and fixed corpuscular elements.

This description of the incorporation and diffusion of a malignant tumor in the system somewhat anticipates my general plan. Metastasis and cachexia are properly deuteropathic symptoms. A more complete system of arrangement will be possible in the Second Part.

II. THE ANATOMICAL DISTRIBUTION

OF DISEASE.

DEUTEROPATHIC GROUPS OF SYMPTOMS.

INTRODUCTION.

The anatomical changes which accompany the local outbreak of disease are communicated to the adjacent organs or to the entire system. Thus arises a secondary class of symptoms, which we will term deuteropathic. The propagation of disease is, accordingly, direct and physical (anatomical), and is consummated in various ways. It is of prime importance to know whether the original seat of disease generates and throws off products, which, by the inter-communication of the lymphatics and blood vessels, are transmitted to the system at large. These products may be coarsely constituted, like aggregated or isolated cells, detached fragments of coagulated blood, etc., in which case they are liable to collect in narrow and impassable blood vessel channels and produce what is known as metastasis.

If, however, the products should be of a minute, liquid, or even volatile nature, we may expect them to become intermixed with the blood and juices of the body.

The reception and propagation of such a "materies peccans from a seat of disease resembles, in many respects, the reception and propagation of organic or mineral poison, infectious matter, etc.; both processes often give rise to similar results. As one of the chief of these, we may reckon the production of fever. The central nervous system, being especially sensitive to blood-poisoning, exhibits certain general symptoms of excitation and exhaustion, which form another typical group. At last the anatomical composition of the blood begins to suffer from this constant admixture of foreign elements, and this deterioration, joined to the loss of cells and juices in the seats of disease, results in a general decline, or a cachexia of the body.

A local affection is also propagated anatomically through a direct attack upon the nerves of the diseased part. Every process of inflammation and reproduction claims a certain amount of space for its solid and liquid products. The space furnished by a closed parenchymatous organ is soon filled, and every additional deposit leads to a mechanical pressure upon the nerves of the organ. This takes place soonest in organs rich in nerves and deficient in flexibility, as in the serous membranes, periosteum, skin, etc. The local nerve irritation thus produced culminates in pain, and this cardinal symptom may also bring in its train a number of other nervous symptoms, ranging from the slightest sympathetic affections to the most severe neuralgias and cramps.

METASTASIS.

When a local disease, which is of some standing and unmistakably primary in origin, is followed by another similar disease in a more or less distant locality, the physician says that the disease has produced a metastasis. The same disease can form not only one, but many metastases, which, in turn, máy again produce metastases, etc. This fact reveals an extensive similarity between all metastasis-producing diseases, for certain appearances are observed which are typical of certain anatomical arrangements, and result from the transmission of disease-producing fragments through the blood vessels and lymphatics.

We can distinguish sharply enough the metastases transmitted by the blood paths from those transmitted through the lymphatics. The lymphatics are so arranged and constituted by nature that they are able to take up even solid fragments, i. e., wandering cells of the parenchyma. A minute subdivision of the corpuscular products in the primary seat of disease is all that is necessary to secure their entrance into and transmission through the lymphatics. The blood vessels, on the other hand, have closed walls, and, in order to effect a migration through them from one seat of disease to another, the product must have been generated within their lumen, have grown through or been forcibly introduced into their walls. For this reason metastasis through the blood vessels shows a certain sameness in the products transmitted. Most important are: blood clots, derived from the veins of the primary growth;

air and fat, which, under particularly favorable circumstances, in the case of fresh wounds, can penetrate into the veins; and, finally, intestinal worms or large pieces of tumor, which, by some accident, have broken into a vein (cancer of the veins). (a) Metastasis through the Lymphatics. It is well known that the art of tattooing, which is not confined, by any means, to Indians alone, is effected by pricking the skin with sharp needles and rubbing forcibly into the fresh wound minutely subdivided, but insoluble dye-stuffs (Cinnabar or Prussian blue.) A part of this dyestuff remains in the connective tissue, the rest reaches the lymphatics, by which it is carried further. Having gained the lymphatic gland, it even penetrates the capsule, but is then arrested. These brilliant particles remain for years in the terminal bulbs of the lymphadenoid tissue, partly closed in by cell protoplasm and fibrous tissue. The material is apparently too heavy and rough to pass unarrested through the fine and convoluted lymphatic paths into the interior of the gland. The same happens to all minutely subdivided particles which have in any way entered the lymphatic vessels at some point on their periphery. The effect of these intrusions into the lymphatic ducts is, of course, very different from the simple tolerance of the gland substance for all those unchangeable and consequently chemically bland particles, like coal-dust, iron-dust, stone-dust, etc.

Some of the wandered-out, colorless blood corpuscles are invariably carried from an inflamed centre to the neighboring lymphatic glands. In consequence of this, the local lymph paths swell so quickly and to such an extent that the secondary (deuteropathic) suffering really exceeds the primary (protopathic). The nerve sheaths being particularly pressed upon, pain results, which is increased by the slightest touch or movement of the neighboring organs.

As the inflammation diminishes, the swelling of the local glands also subsides. The cells which have wandered in have meanwhile either found their way out or been overtaken by fatty degeneration. Often, however, things do not run so smoothly. The irritated gland becomes inflamed, and the formation of pus and abscesses inevitably follows. We must, then, provide for an early evacuation of the pus, lest this metastatic centre again cause others.

We have already laid stress upon the fact that the metas

tasis of malignant tumors by means of the lymphatic system is very prominent.

(b) Metastasis through the blood vessels. We have mentioned above, briefly, the conditions necessary to a metastasis through the blood vessels. The blood vessels, according to Harvey's memorable discovery, are completely closed in, and not intended for the reception of solid particles of the bodily parenchyma; hence, only such solid bodies can be transmitted from one point to another, as have been produced in the lumen of the blood vessel, or have been forcibly introduced through their walls. Whence the extreme rarity of cases of metastasis of heterogeneous substance. We will first consider the metastasis of blood clots, which have been formed in the blood-vessel apparatus, and carried away by the blood current, and also examine the doctrine established by Virchow concerning thrombosis and embolism of thrombi.

COAGULATION OF STAGNATING BLOOD.

Blood coagulates so soon as it is cut off from the general circulation and becomes stationary. If we open a vein in an animal, catch the blood in a glass, and allow it to remain stationary for a few minutes, we notice that the blood is transformed into a dark red jelly, which, in the course of a day, gradually sinks to the bottom of the glass, having diminished one-fifth in volume. In the meantime, a yellowish-colored clear liquid collects above the clot, and if evaporation is prevented, rises in the glass to the original level of the blood. The fibrin has coagulated, and with it the blood corpuscles are fixed; then, having contracted upon its contents, a portion of the blood serum has been squeezed out.

By the use of the microscope, we learn the following concerning the process:

Let us suppose a drop of blood taken from the finger, allowed to run into the capillary space between a glass slide and thin glass cover, and placed immediately under the microscope. At once, even while the blood corpuscles are settling, we see that peculiar aggregation which leads to the formation of the well known rouleaux and other less marked shapes. In the course of ten or fifteen minutes, those groups and chains of blood corpuscles unite and form a kind of network of red bands with intermediate circular gaps. The whole resembles a coarse sponge, and it is, undoubtedly, this sponge, formed also largely