Ointments, Salves, and Cerates. Ointments are unctuous preparations, that merely differ from cerates in consistence, being made and used in a similar manner. Their solidity should not exceed that of good butter, at the ordinary temperature of the atmosphere. When the active ingredients are pulverulent substances, nothing can be more suitable to form tho mass of the ointment than good lard, free from salt; but when they are fluid, or semifluid, prepared suet, or a mixture of suet and lard, will be necessary to give a proper consistence to the compound; in some few instances wax is ordered for this purpose. Glycerine is now frequently prescribed in ointments, and is difficult to mix. Suppose it be ordered with zinc ointment, as is often the case, do not use ready-made zinc ointment, but weigh the proper quantity of oxide, rub the glycerine with it, and then add the lard. This makes a good smooth ointment which does not separate. Of course, the same plan can be adopted with any other powder. If there be no powder, melt the ointment, but do not let it get too hot, and beat the glycerine in and stir till cold; it then mixes much better; but still, if there be a large proportion of glycerine, it will separate after a time. (See No. 5009 (Schacht's Glycerine of Starch, or Plasma), etc..) Unctuous preparations may be prevented from getting rancid, by dissolving in tho fat a little gum-benzoin or benzoic acid. The term cerate is applied to those unguents which contain wax. A number of these preparations are given here, and others will be found, by referring to the Index, under their respective headings.

4932. Simple Cerate

4932.    Simple Cerate. Melt together 8 ounces lard, and 4 ounces white wax, stirring constantly until cold. ( U. S. Ph.)

4933. Spermaceti Cerate

4933.     Spermaceti Cerate. Melt together 2 ounces spermaceti, 8 ounces white wax, and 1 pint warm olive oil, and stir assiduously until cold. This is used as a soft cooling dressing. As soon as the materials are melted, they should be moved from tho fire, strained into a clean vessel, and stirred until cold. To facilitate the cooling, tho vessel may bo placed in cold water or a current of cold. air. This will render the product both whiter and finer than when allowed to cool by itself. The operation of melting should be performed in a water-bath. On the large scale lard or suet is substituted for oil, by which means less wax is required. The following is a good form where a cheap article is wanted : Clarified mutton suet, Si-pounds ; white wax and spermaceti, of each 3/4 pounds. As above.

4934. Chilblain Ointment

4934.    Chilblain Ointment. Take of gall-nuts, in very fine powder, 1 drachm avoirdupois; spermaceti cerate (see No. 4933 (Spermaceti Cerate)), 7 drachms; mix, add pure glycerine, 2 drachms, and rub the whole to a uniform mass. An excellent application to obstinate broken chilblains, particularly when used as a dressing. When the parts are very painful, 1 ounce of compound ointment of galls may bo advantageously substituted for the galls and cerate ordered above. (See No. 5003 (Compound Resin Cerate).)