Druckschrift 
The Edinburgh new Dispensatory : containing 1. The Elements of pharmaceutical Chemistry ; 2. The Materia Medica; or the natural, pharmaceutical and medical History, or the Substances employed in Medicine ; 3. The pharmaceutical Preparations and Compositions ; including Translations of the Edinburgh Pharmacopoeia published in 1805, of the Dublin Pharmacopoeia in 1807, and of the London Pharmacopoeia in 1815
Entstehung
Seite
634
URN (Seite)
  
Rechtsdrehung 90°Linksdrehung 90°
  
  
  
  
  
 
Einzelbild herunterladen
 

684

Preparations and Compositions. Part III.

I

h

I*

I

Chap. XLL-LINIMENTS, OINTMENTS,CERATES, axd PLASTERS.

These are all combinations of fixed oil, or animal fat, withother substances, and differ from each other only in consis-tence. Deyeux has, indeed, lately defined plasters to bo com-binations of oil with metallic oxides; but as this would com-prehend many of our present ointments, and exclude manyof our plasters, we shall adhere to the old meaning of theterms.

Liniments are the thinnest of these compositions, being on-ly a little thicker than oil.

Ointments have generally a degree of consistence like thatof butter. Jj-

Cerates are firmer, and contain a larger proportion of wax.

Piasters are the most solid, and derne their firmness, ei-ther from a large proportion of wax, ro?in, &cT or from thepresence of some metallic oxide, such as that of lead.

Plasters should have such a consistence as not to adhere tothe fingers when cold, but become soft and plastic when gent-ly heated. The heat of the body should render them tenaciousenough to adhere to the skin, and to the substance on whichthey are spread. When prepared, they are usually formed intorolls, and inclosed in paper. Plasters of a small size are oftenspread on leather, sometimes on strong [taper, or on tinfoil,by means of a spatula gently heated, or the thumb. The lea-ther is cut of the shape wanted, but somewhat larger ; andthe margin all around, about ^ inch in breadth is left ufteo-vered, for its more oa^y removal when necessary! Linen isalso used, especially for the less active piasters, which areused as dressings, ami often renewed. It is generally cutinto long slips, of various breadths, from one to six inches.These may cither be dipt into the melted plaster, and passedthrough two pieces of straight smooth wood, held firmly to-gether, s< as to remove any excess of plaster; or, what ismore elegant, they are spread on one side only, by stretch-ing the linen, and applying the plaster, which has been melt-ed and allowed to become almost cold, evenly by means ofa spatula gently heated, or, more accurately, by passing the

 
Seiten anSeiten aus
Text aus