Emplastrum Cantharidis Vesicatoriae Compositum. Edin. Compound Plaster of Spanish Flies

"Take of Venice turpentine, eighteen parts; Burgundy pitch, blistering flies, of each twelve parts; yellow wax, four parts; subacetate of copper, two parts; white mustard seeds, black pepper, of each one part. Melt the Burgundy pitch and the wax, and add to them the turpentine. While these remain still warm, after being melted, sprinkle in the other ingredients, reduced to fine powder, and mix them, stirring constantly, so as to form a plaster."

This plaster is intended to raise a blister more quickly than the former: thence it is adapted for cases of gout and cramps of the stomach, in which the effect of the blister must be almost instantly produced. Its operation is accompanied with great pain, and a pungent sense of heat: it is apt to cause very unpleasant ulceration if allowed to remain too long applied.1

Emplastrum Cerae. Lond. Wax Plaster

"Take of wax, suet, of each three pounds; resin, a pound. Melt them together, and strain."

Emplastrum simplex, Edin. Simple Plaster.

1 Blisters are rapidly raised by a solution made by digesting cantharides in acetic aether, in the proportion of 3 j. of the powdered flies to f j. of the aether. They are still more quickly raised by the application of boiling water.

"Take of yellow wax, three parts; mutton suet, white resin, of each two parts."

These plasters were originally intended for dressing blistered parts, with the view of promoting a discharge; but, owing to the pain and irritation they induce, they are now seldom employed.

Officinal preparation___Emplastrum Cantharidis, L.

Emplastrum Galbani. Lond. Galbanum Plaster

"Take of galbanum, eight ounces; plaster of lead, three pounds; common turpentine, ten drachms; resin of the spruce-fir, powdered, three ounces. Add first the resin of the spruce-fir, then the plaster of lead, melted with a slow fire, to the galbanum and turpentine melted together, and mix the whole together."

Emplastrum Gummosum, Edin. Gum Plaster.

"Take of plaster of semivitreous oxide of lead, eight parts; ammoniacum gum-resin, galbanum, yellow wax, of each one part. Add the gum resins to the melted plaster and wax, and mix."

Emplastrum Galbani, Dub. Plaster of Galbanum.

"Take of litharge plaster, two pounds; galbanum, half a pound; yellow wax, sliced, four ounces. To the galbanum melted by heat, add the litharge plaster and the wax; then melt the whole together by a gentle heat."

These plasters are stimulant and suppurative. They are applied with advantage to scrofulous tumours; to joints long affected with arthritic pains; and to the loins in rickets; as a suppurative to excite indolent tumours, and reduce the induration which often remains around discharged abscesses.

Emplastrum Hydrargyri. Lond. Mercurial Plaster

"Take of mercury, three ounces; plaster of lead, a pound; olive oil, a fluid drachm; sulphur, eight grains. Add the sulphur gradually to the heated oil, stirring constantly with a spatula until they unite; afterwards rub the mercury with them until the globules disappear; then add by degrees the lead plaster melted with a slow fire, and mix the whole."

Edinburgh.

"Take of olive oil, resin, of each one part; mercury, three parts; plaster of semivitreous oxide of lead, six parts. Rub the mercury with the oil and the resin previously melted together, and cooled, until the globules disappear; then add gradually the plaster of semivitreous oxide of lead melted, and let the whole be carefully mixed together."

Syn. Quecksilberpflaster (G.).

The mercury in these plasters is supposed to be in the * state of oxide, with a minimum of oxygen; and the sulphur and oil, are intended to diminish the labour required for this oxidizement of the metal. The plasters are powerful dis-cutients, and are applied to buboes, venereal tumours, nodes, when they are not very painful to the touch, and indurations; they are also applied to joints affected with obstinate syphilitic pains.