It is improper in weak exhausted patients, and in erysipelatous ulcers, cancers, and some similar complaints. Among its bad effects may be mentioned, excessive debility and irritability, decayed teeth, weakened stomach and intestines; but, above all, what is styled by Mr. Pearson, erythismus. It is a state of debility, with the powers of circulation exhausted, perhaps, by too long or constant exercise; a slight exertion proves fatal, seemingly from a defect of circulation in the brain.

Of the choice of the preparations we have little to add. The most useful errhine and emetic is the mer-curius vitriolatus: the most effectual laxative, calomel: the most serviceable alterative, muriat of mercury. It is this preparation that gives efficacy to the popular alteratives styled vegetable; and the contrivers hope to elude detection by the density and the colour of the preparation. The metal may, however, be discovered by inspissating a large quantity, and adding ammonia. In this state the mercury will, by rubbing, whiten bright copper: in the minute proportion employed it eludes every other test.

In venereal complaints, the mercurius calcinatus or calomel are the most effectual preparations; but perhaps the mercurial ointment, rubbed in externally, is still better. In internal visceral obstructions; and in external indolent tumours, (scrofulous ones excepted,) the ointment is the best remedy: in chronic rheumatisms the calomel has been preferred: in enlargements of the prostatae, and similar indurations internally, the corrosive sublimate.

It hath been swallowed crude, as an universal remedy.

Dr. Dover and Dr. Cheney commend it in the following disorders:

"1. Joined with the gum guaiacum and a little aloes, it hath been successfully used in the erysipelas, gout, and defoedations of the skin.

In hysteric complaints its advantages arc considerable, if joined with the bark, valerian, aloetic, or the gum pills, as circumstances may require.

"3. In conjunction with preparations of iron, it succeeds in suppression of the menses.

"4. In intermittents it avails when joined with the bark and iron.

"5. In ophthalmies it hath been effectual when accompanied with millepedes and laxatives.

"6. The hydrargyrus cum creta, joined with gum guaiacum and the antimonial wine, does wonders in chronical rheumatisms.

"7. In the jaundice, sciatica, and anasarcous dropsy, the hydrargyrus cum creta is successful to admiration."

Arid to these of Dr. Cheney may be added, that old foul ulcers are sometimes brought to digest by its use.

"The hard bellies of children are relieved by it, if accompanied with such other medicaments as the particular case may require.

"By boiling two or three ouncesof quicksilver in four pints of water to two pints, and using the clear liquor for common drink, it destroys worms.

"And in the venereal disease it is by many considered as a specific.

"The true secret of curing diseases with mercury is to cause it to circulate with the blood as long as possible, without producing any evacuation at all.

"A long use of quicksilver weakens the habit, and so should be accompanied with mild antimonials, the bark, or sarsaparilla, etc. as circumstances seem most to require."

Quicksilver is divided by earthy powders, balsams, mucilages, etc.; but with nothing more advantageously than the mucilage of gum arabic. Mr. Plenck, of Vienna, directs a drachm of it to be mixed with two drachms of gum arabic in powder, by degrees to add a little water, and to continue the trituration of them together until the globules totally disappear. This is called mercurial mucilage; to which half an ounce of any syrup, and half a pint of water may be added, and two common spoonfuls of the mixture may be taken every night and morning in such cases as require its use.

Gum arabic is supposed to powerfully restrain the mercury from running off by the salivary glands; and if a salivation is already excited, it may assist, like any other mucilaginous substance, in checking it.

Crude quicksilver in general is of equal advantage with any of its preparations; yet, in particular con--iiitutions, one or other of them may demand a preference.

Argentum mobile, et fusum. See Argentum Vivum.

argentum mobile, et fusum. See Argentum Vivum.

Argentum miratum. See Argentum.