* I have not unfrequently met with eczema in dogs and cats, but have never seen it in cattle, sheep, or horses.

By empirical treatment, I mean the use of such remedies as experience has shown to be useful, independent of any theoretical views as to their mode of action. Those which have hitherto proven most serviceable are the ones which appear to exert a direct and specific influence on the skin itself, as evidenced by the cutaneous lesions which result from their long-continued and excessive use. Chief among these is Arsenic. No one can peruse pages 23 and 24 of this book without becoming sat fied that arsenic is a decided cutaneous stimulant when given in the ordinary therapeutic doses.

If arsenic is administered in eczema in ordinary doses (Say Iij x. of Fowler's sol.) the behavior of the eruption will depend very greatly upon its condition as regards the degree of inflammatory action present. Most authorities agree that in cases of acute eczema, arsenic, given as above, will increase the inflammation and irritation, and generally aggra-vate the trouble. With them the chief field for the use of arsenic is in subacute and chronic conditions, and more especially when the disease is in the third or scaly stage. Under these circumstances arsenic, properly administered (that is in full doses), certainly exhibits a marked and decided curative effect, and this effect will become manifest with a prompt-ness proportionate to the size of the dose. Its best effects seem to occur at the verge of tolerance, just before the drug begins to declare its energy on other parts of the body. This limit of tolerance is manifested irritation of the conjunctivae, swelling of the eyelids, gastric irritation, and perhaps swelling of the feet, and sometimes temporary albuminuria.* It is, however, somewhat an open question whether it is better to reach the limit of tolerance quickly or gradually, that is, whether the commencing dose shall be five or ten minims of Fowler's solution, or whether it shall be two or three minims gradually increased. The drug, at all events, should be given well diluted and just after a meal, never on an empty stomach. Mr. Hunt's rules on the subject have already (p. 26) been given. The preparation of arsenic to be used is not, 1 believe, a matter of indifference. My own preference is for Arsenious acid itself, rather than its alkaline salts (see p. 27).

It is not, however, in subacute eczema alone that arsenic is capable of being made useful. In the acute forms also it can sometimes be fin-ployed to advantage. It is simply a question of dose. As before stated arsenic given in the usual doses will generally aggravate an acute eczema, but if the dose be diminished to one-fifth, one-tenth, or one-twentieth the ordinary amount, it will no longer aggravate, but, on the other hand, by gentle stimulation exert a decidedly alterative and beneficial effect. The most desirable dose in a given case can only be arrived at by experimentation, commencing with a small one and diminishing it if necessary, or commencing with a very small one, and increasing it, if no effect, either good or bad, is apparent. The slightest aggravation of the eruption that appears to be due to the action of the drug calls for its immediate suspension, or further continuance in still smaller doses.

* I always closely watch the urine of patients taking large doses of arsenic, and discontinue It on the slightest indication of renal irritation.

Where arsenic fails to relieve the eruption, or where for any reason it is contraindicated, Tar may sometimes be used to advantage, especially in dry chronic forms. The Pix Liquida of the pharmacopaeia may be given in doses of from two to five grains three times a day, the dose to be gradually increased to the limit of tolerance, which usually manifests itself by symptoms of gastro-intestinal irritation, and sometimes by a slight efflorescence on the skin.

Carbolic acid appears to be analogous in its action to tar, and may also sometimes be given to advantage in the same forms of eczema.

Phosphorus, as specially recommended by Broadbent, is undoubtedly of service in long-standing eczema. Its modus operandi, however, is obscure. Its direct action on the skin appears to me to be slight, while its known affinity for the liver, warrants the inference that it chiefly acts in virtue of its power as a hepatic stimulant. The dose of phosphorus may vary between 1/100 and 1/25 of a grain, and should never, I think, exceed the latter amount. I, of course, refer to reliable and active preparations of phosphorus, and not to such as from age or improper preparation have lost much of their activity. The most eligible forms for the administration of this drug are the one per cent. solution of phosphorus in oil, or some of the ready-prepared pills of the market. The activity of these, however, should not be assumed on the strength of the manufacturer's guarantee, as I have several times met with phosphorus pills which, on examination, exhibited no trace of active phosphorus. A good pill, on being cut in two, gives out a strong phosphoric odor, and if it be scraped a little with the point of a penknife, in a dark place, will display marked phosphorescence.

Cantharides is recommended by many authors, more especially the French. My own experience with it is too limited to enable me to speak confidently as regards its value. The tincture well diluted is the most eligible form for its administration, and a commencing dose of two or three drops may be gradually increased to ten or more. Of course strict watch should be maintained lest urinary irritation or severe vesical trouble seize the patient unawares.

The foregoing remedies are chiefly of service in chronic cases. In acute cases, especially at the very beginning, I have seen prompt change for the better, I might almost say abortion of the eruption follow the use of small doses of Rhus Toxicodendron. The remarkable susceptibility displayed by some to the effect of this poison, even in a state of extreme dilution, is evidenced by the occurrence of the Rhus eruption in persons who have simply come near, without being in direct contact with the plant, warn us that the dose should be exceedingly small. The 1/100 of a drop of a good tincture or even a less amount is not too small a dose to commence with, as I am satisfied by abundant personal experience.

In both acute and chronic cases of a pustular character - the Impetigo of the older writers - when the suppuration is abundant, the Sulphide of Calcium will often prove of service. This condition is more frequently met with in children than in adults, and the doses that I have found of service varied from 1/100 to 1/25 of a grain. The smaller doses are best adapted to acute, the larger ones to subacute conditions.

Lastly among the empirical drugs Viola Tricolor must be mentioned. This drug has already (p. 113) been discussed. In eczema capitis, acute or chronic, and especially in children of a lymphatic nature, this drug exhibits such prompt effects (good or bad) that we need not wonder that the writers of the last century considered that it had a specific influence in this disease. As before stated, if given too freely or in too large doses, it very often aggravates the patient's condition, as evidenced by increased heat irritation, and exudation. In chronic cases this aggravation is often desirable; in acute cases it should never be induced if it can be avoided. The temporary aggravation of the subacute eruption by the internal use of Viola tricol. accomplishes much the same result as we sometimes seek to bring about by the external use of strong alkaline and other irritant applications. On withdrawal of the irritant the aggravation is succeeded by a reaction which results in an improved condition of the eruption. In subacute cases then the dose may be large, but in acute ones it should be quite small.