The hypodermic method distinguishes itself from all, or nearly all others, by qualities of such striking importance that in a majority of cases they overbalance all disadvantages, which the method may otherwise present. It offers us rapidity of action, constancy and great intensity and absolute security as far as physiologcal and therapeutic effects are concerned, since we are certain that all we wish to introduce, has been introduced. Besides, by the aid of exact doses we arrive at a degree of preciseness which it is impossible to attain in any other way.a

The substances employed are chiefly alkaloids in solution, and it may be said in a general way that the remedies should be the purest active principles of the medicament. The solution must be carefully preserved. After a time all hypodermic solutions become turbid; this is not due to a precipitation of active substances, but to the presence first of spores, then simple filaments, which finally ramify and which are formed by a low order of vegetation belonging to the germs leptomitus. They are filamentous algae. These algae develop in a rapid, and in one sense destructive manner in all solutions which have stood for some time. They cause the disappearance of a certain quantity of the active substance, and besides, act the part of foreign bodies, or greatly reduce the strength of the solution to be used. Any of the anti-zymotics will prevent this development. a Among those of a harmless nature is borax. b The hydrolate of eucalyptus, glycerine, or bay-cherry, salicylic acid, c benzoic acid; d but phenic acid even in the proportion of one-thousandth is better because it is beyond all comprehension, more active.a

In administering an injection, you must not operate on the basement layers of the dermis and in those areolae which contain more or less globular masses of an adipose cellular tissue; this would give rise to eschar, inflammations, and deep-seated furuncles. You must penetrate into the subjacent laminated cellular tissue, must reach the superficial and even the deep seated faciae superficialis.a

In administering a hypodermic injection, the greatest energy is exerted on the region in which the deposit has been made, and in its vicinity. And experiments have proved that the effects from an injection may vary in different localities, as has been demonstrated in the inoculation of a virus. In experimental charbon, for example, we have an affection in which we may observe every degree of intensity in accordance with the variation of the germ, or the soil. In certain cases it is only necessary to vary the place of inoculation in order to get entirely different symptomatology. In the inoculation of contagious peripneumonia, for example, if the liquid is introduced under the skin of the thorax, the animal dies in a few days. If the inoculation is made under the skin in the region of the tail, where the tissues are more compact, we obtain aprof. Adolph Gubler. clumonsin bdumas. dgosselin a vaccination of simple local gangrene; finally, if the liquid is introduced into the trachea (under the protective action of the kidneys), no symptoms follow, nevertheless, the animal is really vaccinated, and will afterwards have immunity from the malady. We see that great difference of effect arises in accordance with the point of inoculation adopted.

It is to the epigastric region that substances should be applied, when intended to act upon the bulb of the aorta, as there exists an intimate connection from a functional point of view, between the epigastric region and the bulb, and when it is necessary to act upon the bulb, for the purpose of putting an end to syncope it is there we must address the effects. If for example, you are called upon to attend persons laboring under collapse, caused by an excess of chloroform, it is upon that organ that you are to bring all revulsives to bear, and chiefly electricity. The same may be said of medicamental substances to be introduced under the skin for the purpose of acting upon the bulb itself. b

The injection of active substances are possessed of highly irritating qualities; this is the case with mercurial salts. b When even small proportions are introduced, they may give rise to little phlegmons and furuncles, and even, in some cases. to gangrene. It would be discouraging if these accidents were of frequent occur-rance. Mercurial salts have been combined with albumen. Other albuminoid substances, like gluten and legumine, might be used. To obtain that result, bi-chloride is added to an albuminous solution; an albuminate of proto or bi-chloride is formed, according to the salts used, and under this form metallic substances lose almost the whole of their nocent qualities. b

The injections of aconitine cannot become of a general use because of the intense hot and burning sensation they produce. This alkaloid does not offer any great difference as to intensity of effect whether introduced under the skin or given through the digestive organs. Picro-toxin is not felt, but always produces a node. Emetine is not a real agent of the hypodermic method; it can only be used as an irritant, and to produce a deep eschar.b Injections into arteries in most cases are extremely painful.c

There are substances which are directly soluble, but very irritating, like phenic acid, creosote and perchloride of iron. These cannot be introduced by the hypodermic method, because they would cause phlegmons.

Quinine when introduced under the skin in small quantities, if it chance not to produce an inflammatory condition causing an obstacle to absorption, it determines the same physiological and therapeutical effects as quantities four or five times greater given through the stomach.b This difference in the dose varies in different medicaments; in some it is the same, and of several very powerful substances, less would be required than if administered by the stomach. Let us suppose that you rapidly introduce into aprof. Brouardel. bprof. Adolph Gubler. cl. Hermann.

the blood phosphorus, oxide of carrion, nitrite of amyl, anaesthetics - in fact any of those substances which act directly on the blood. They will act, producing what we might term lightning stroke. If you happen to introduce them by the subcutaneous method, and they come into the circulation in large masses, they will produce effects nearly as violent as by inhalation. And there will be the widest difference between the effects produced hypodermically and by way of the stomach.

One of the main objects in resorting to hypodermic injections is to secure its analgesic effects. You may introduce under the skin a substance like strychnine which excites, or aconitine which burns, or morphine which narcotizes, or even pure water or distilled water, and in every case after a given time analgesia will surely follow, as an invariable result.

Atropine has been more frequently used hypodermically than any other remedy, and in proportion has done more harm and good than any other.

The primary dose of a salt of morphine should never exceed one-eighth of a grain.a This dose may prove dangerous in some cases. There is on record, where a somewhat corpulent patient, with organic, probably fatty disease of the heart, sunk at once under profound and fatal coma after the subcutaneous injection of one-eighth of a grain of morphine.b

The prompt and speedy relief afforded by morphine subcutaneously. in cholera morbus, is in singular contrast with its well attested inefficiency, or even deleterious effects in epidemic cholera, and cholera infantum, at least after the very early stages are passed.b