In enteric or typhoid fever, I habitually use mercury in the second stage, whenever a commencing dryness of the mouth calls for something more than the refrigerant and diaphoretic remedies applicable to the earlier symptoms. There is usually, with this dryness of the mouth, dryness also of the skin, with scantiness of the urine, showing a general deficiency of the secretions. Through the disintegration of the tissues, the blood is constantly receiving impurities, which, not being carried off by the secretions, accumulate in the circulation, and probably aid in causing that depraved condition of the blood, which characterizes the advanced stage of the disease. Mercury is thus called for, as a secretory stimulant, in order to obviate this effect; and, as its influence on the secretions is general, and at the same time mild, it is probably better adapted for the purposes of elimination than more active medicines directed to a special function; while it may less endanger depression. Another strong indication for the use of mercury is offered by the affection of the intestinal glands, which constitutes one of the chief sources of danger, and, as I think from a good deal of experience, is favourably modified by the mercurial impression. it has seemed to me that the subsequent course of the disease has been generally more favourable, when I have had the opportunity of using this remedy in the second stage, than in cases where this opportunity has not been afforded. Still another reason for the practice is the frequent complication of bronchitis, and the occasional occurrence of pneumonia, in both of which the mercurial influence is beneficial. in general, the plan should be commenced about the eighth or ninth day of the disease; one grain of the blue mass being given every two hours, with one-sixth of a grain of ipecacuanha, should the stomach not be irritable, and about the same quantity of opium, if required to check the diarrhoea. As soon as the gums are in the slightest degree touched, the medicine should be diminished, and afterwards so managed as to sustain the same amount of impression so long as required. if the tongue become moist and remain so, the plan may be continued till convalescence shall take place; but if, notwithstanding its use, complete dryness of the tongue supervene, I abandon the use of it, and have recourse to the oil of turpentine.* d. Various Uses. - There are several affections, usually ranked among diseases, in which mercury, on some one of the principles already stated, often proves very useful, and which require a brief notice.

In dropsy the remedy sometimes exercises extraordinary powers; but discrimination in its use is important. When the affection is dependent on an anemic state of system, or is associated with that form of Bright's disease which consists in fatty degeneration of the kidneys, it is strongly contraindicated. in the cases which originate in incurable organic affections of the liver or heart, it can be of no use, while it may do harm by impairing the general strength. But, whenever the dropsy arises from chronic inflammation of the liver, from valvular affections of the heart consequent on fibrinous exudation, or from inflammation or high vascular irritation of the pleura, pericardium, peritoneum, or cerebral meninges, mercury may be combined very advantageously with the diuretics employed, especially squill and digitalis. Hence, it is generally better adapted to ascites, hydrothorax, and hydrocephalus, than to anasarca, though the rule is by no means absolute. Calomel and squill in combination have long been noted for their efficiency in thoracic dropsies. Of course, little good can be expected from the remedy in dropsies, dependent on serous inflammation or irritation, caused by tubercles diffused through the membranes. it is now generally thought that mercury is not appropriate to the dropsy of Bright's disease in any of its forms. But when it is connected with inflammation of the kidney, as indicated by fibrinous casts in the urine, without any evidence of fatty degeneration, I should have no hesitation in resorting to mercurializa-tion, should the disease not yield to other measures.

Palsy occasionally affords indications for the use of mercury. Whenever there is reason to believe that the disease has been caused, or is kept up by inflammation whether of the spinal marrow, the cerebral centres, or the nerves themselves, and the inflammation refuses to yield to depletory and revulsive measures, a slight and sustained mercurializa-tion should be tried, and will probably be found serviceable. The same in the poisonous effects of lead, whether in the form of lead colic or lead palsy, mercury has been imagined to exert a sort of antidotal power, and has been much used with supposed advantage; but it is likely to be superseded by alum and iodide of potassium in these affections. Nevertheless, it may be resorted to, with some hope of benefit, in cases which have resisted these medicines.

* I wish it to be understood that I do not consider mercury as desirable in all cases of this disease. There are many in which the symptoms, throughout, are so mild that the remedy is not called for; and I would reiterate that, in no case should the mouth be allowed to become very sore; the slightest sign of the action of the mercurial on the system, whether in the odour of the breath, the increased flow of saliva, or the whitish opacity of the gums, their tenderness, or their redness at the edges, being sufficient to indicate that the medicine should be suspended or withheld. (Note to the second edition.) may be said of other nervous affections, as neuralgia, epilepsy, chorea, hysteria, and even insanity. in a special form of the last-mentioned affection, connected with or dependent on chronic meningitis, a moderate and persevering use of mercury, with revulsives, offers the best chance of a favourable result. in hypochondriacal feelings and delusions, the same remedy may prove useful by correcting disorder of the hepatic function. Some of these nervous affections, moreover, are occasionally mere concealed forms of syphilis, and yield to mercury most happily, after having resisted other means. Examples of the kind we sometimes have in neuralgia; and paroxysmal convulsions resembling epilepsy have been traced to a syphilitic origin, and been promptly cured by this medicine.

Indeed, the remedial influences of mercury are so various and effective that, in any obscure malady, not presenting obvious contraindications, the practitioner would be justified in the careful use of it, in the hope that he might thus cut off the concealed root of the disease, and in the confidence that, if he failed to accomplish his object, he would at least, with due caution, inflict no serious injury.

i have not treated of the various applications of mercury as an exclusively topical agent, preferring to do this in connection with the several preparations thus used.