These are unctuous compositions, possessing a certain degree of firmness, intermediate between that of plasters and that of ointments. Their consistence depends on the wax they contain; and from it they derive their generic appellation. The most important circumstance to be attended to in their preparation is the freshness of the fat and the oils employed : and their preservation in this state.

Ceratum. Lond. Cerate

"Take of olive oil, four fluid ounces; yellow wax, four ounces. Add the oil to the melted wax, and strain."

Syn. Cerat simple (F.), Cerotto semplice (I.).

This is an useful simple emollient dressing to excoriations and sores.

Ceratum Calaminae. Lond. Calamine Cerate

"Take of prepared calamine, wax, of each half a pound; olive oil, sixteen fluid ounces. Mix the oil with the melted wax; then remove them from the fire, and as soon as they begin to thicken, add the calamine, stirring constantly until the cerate be cold."

Ceratum Carbonatis Zinci impuri, Edin. Cerate of impure Carbonate of Zinc.

"Take of simple cerate, five parts; prepared impure carbonate of zinc, one part. Mix."

Unguentum calaminare, Dub. Calamine Ointment.

"Take of ointment of yellow wax, Jive pounds; prepared calamine, a pound. Make them into an ointment."

These preparations are very useful dressing to excoriations and ulcers; and as they are in some degree desiccative, they are also applied to burns after the inflammation is abated; and to the eyelids in ophthalmia tarsi. They have been long known in practice under the name of Turner's Cerate.

Ceratum Cetacei

Lond. Spermaceti Cerate. ."Take of spermaceti, two ounces; white wax, eight ounces; olive oil, a pint. Add the oil to the spermaceti and the wax melted together; and stir them until they be cold,"

Ceratum Simplex, Edin. Simple Cerate.

"Take of olive oil, six parts; white wax, three parts; spermaceti, one part. Melt the wax and spermaceti in the oil, with a gentle heat; then keep constantly stirring, until the mixture stiffen in cooling."

Syn. Cerat de blanc de baleine (F.), Cerotto di Spermaceti (I.).

These are soft cooling dressings.

Officinal preparations. - Ceratum Cantharidis, L. Ceratum Carbonatis Zinci impuri, E.

Ceratum Cantharidis. Lond. Cerate of Blistering Flies

"Take of cantharides reduced to a very fine powder, an ounce; spermaceti cerate, six ounces. Add the cantharides to the cerate softened by heat, and mix them together."

Syn. Cerat de Cantharides (F.), Cerotto di Cantarille (I.).

This cerate is intended to promote a purulent discharge from a blistering surface, without occasioning irritation. In some habits, however, it causes strangury, great pain of the part, swelling of the lymphatics, and so much general irritation as to produce cedematose swellings and erysipelas of the neighbouring parts.1

It is preferable to spread cerates or ointments, intended to keep open issues, on lint; and the dressings should in all cases be renewed once in twenty-four hours.