This may be induced in two methods; either rapidly, by large closes at once, or more gradually and safely, by small doses more or less frequently repeated. The effect is very complicated; the most prominent phenomena being sore-mouth with salivation, excitement of the circulation, increase of the secretions generally, a more rapid absorption, more or less disturbance of the digestive function, and a greater sensitiveness of the nervous system. Each of these effects requires a separate notice.

Salivation

Ptyalism. The first phenomenon presented is often a whitish appearance of the lower gums, probably owing to opacity of the epithelium. Soon afterwards the gums are seen to be somewhat swollen, rising up between the teeth, and reddened at their edges. At the same time, they are somewhat tender to the touch; and not unfrequently pain is produced at the roots of the teeth, by firmly closing the jaws. in some instances, pain in the throat on swallowing is the first sign of the action of the medicine. A metallic taste, as of copper in the mouth, is also among the first symptoms; and I have been repeatedly able to detect the approach of salivation by the peculiar fetor of the breath, before any other sign had presented itself. it not unfrequently happens that the above symptoms have existed for some time, before any increase of saliva appears; and occasionally there is at first even a dryish condition of the tongue. Sometimes, however, though rarely, the salivation or ptyalism has precedence of all the other phenomena. There is also an increased production of mucus in the mouth and fauces.

For therapeutic purposes, there is no occasion for any greater effect on the mouth than as above described; but not unfrequently, even when all due caution is observed, the affection is considerably increased. The gums, tongue, cheeks, and fauces, one or all, swell and become painful; deglutition is painful; the teeth, if carious, begin to ache; the tongue is somewhat furred, and indented by the teeth at its edges; the saliva is discharged copiously; the salivary glands swell, together with the neighbouring areolar tissue; and the breath is very offensive, having a peculiar fetor which distinguishes the mercurial sore-mouth from all other analogous affections.

Beyond this point the sore-mouth should never be allowed to proceed, if it can possibly be prevented. But, if the medicine be persevered with, or has originally been given in too large a dose, and in very susceptible persons even from small doses, the affection sometimes becomes greatly aggravated, and, in its severest grade, may be considered poisonous, as it is not without danger. The swelling internal and external increases; the tongue sometimes projects from the mouth, in consequence of its greatly augmented bulk, and is covered with a very thick, soft, yellowish-white fur, extremely offensive to the smell; the parotid and submaxillary glands become much enlarged and painful; the patient cannot open his jaws, swallows with great difficulty and pain, and is wholly unable to articulate; the head requires to be supported on a pillow, and the saliva runs in streams from the mouth; the odour of the breath is insup-portably fetid, and sometimes scents the whole apartment; ulceration of the gums, cheeks, and tongue takes place, with occasionally copious and exhausting hemorrhage; the teeth loosen and fall out; even gangrene of the soft parts, and necrosis of the alveolar processes sometimes occur; and, in not a few instances, death has taken place, or recovery has been attended with revolting or very inconvenient deformity. One of the greatest dangers is from the hemorrhage; though a fatal result may also be owing to the joint effect of gangrene and a depraved state of the blood. I have never, however, witnessed a fatal case of mercurialism; and, with due caution in the use of the medicine, the cases must be extremely rare, indeed, in which such an event can happen. in all my intercourse with medical men, I have heard of but one instance in which the fatal result might not have been avoided; and in that case death was ascribed, whether justly or not I cannot say, to the local effects upon the mouth induced by a few grains of blue mass. This is no argument against the use of mercury as a remedy; for the same might be urged against the most innocent medicines, which, in certain peculiar states of the constitution, may prove highly mischievous. in a person predisposed to cholera, a teaspoonful of castor oil may bring on a fatal attack; and the scratch of a pin has occasioned death from erysipelas or tetanus. The possibility, however, of these tremendous effects from mercury, should teach us always to be most watchfully on our guard against its abuse.

Excitement of the Circulation. Even under the moderate influence of mercury, the circulation is often accelerated; and I have sometimes thought that I could detect an approaching ptyalism, even before any effect had been produced on the mouth, by a peculiar quick, jerking, and irritated movement in the pulse. This direct effect of the medicine on the circulation is much increased by severe sore-mouth; and not unfrequently a fully formed febrile condition is induced, with frequent pulse, headache, furred tongue, loss of appetite, and various nervous derangement.

Increase of the Secretions. This is one of the most prominent and important effects of mercury. Not only is the salivary secretion increased, sometimes enormously; but there is perhaps not one of the secretory functions which is not liable to be similarly affected, though rarely in an equal degree. The hepatic secretion is often energetically stimulated, especially when the medicine is administered internally. There is no Cholagogue which approaches in efficiency some of the preparations of mercury. A true cholera morbus, with copious vomiting and purging of bile, is not unfrequently induced by a large dose of calomel. it has been already stated, that an increased production of this fluid may result from doses of the mercurials, insufficient to cause any other observable effect on the system. I consider this as one of the most certain and best proved effects of mercury; and, though it has been questioned, I have, from personal experience and observation, no more doubt on the point than upon the cathartic property of castor oil. There is every reason, moreover, to believe that the pancreas is stimulated to increased action. it is certain that copious sweating and diuresis occasionally attend the operation of the medicine, though not in general simultaneously.* A soft, rather moist, and relaxed state of the skin is a very common effect. The mucous secretion is also promoted in all the different membranes, but not often very greatly increased, unless in the mouth and fauces.