60 PHARMACY 



Oleum destillatwm, pi. olea destillata. — Distilled oils are obtained by 

 the distillation of flowers, fruits, leaves or seeds of plants; by macera- 

 tion, infusion, expression; or by extraction with solvents. They are either 

 liquid or solid and possess an aromatic odor and taste. They are lighter 

 than water, and soluble in alcohol, ether, and very slightly soluble in 

 water. Distilled oils are miscible with fatty substances and mineral oils. 

 They do not leave a greasy mark on paper. 



Synonyms: Essential oils, volatile oils and ethereal oils. Alcoholic 

 solutions of these oils are known as essences. 



Examples : Oil of peppermint, oil of cloves, oil of wintergreen. 



Oleo-resina, pi. oleo-resinae. — Oleo-resins are semi-solid mixtures of 

 resins and volatile oils. Many are natural products, exuding from trees, 

 as crude turpentine, which contains the volatile oil of turpentine and a 

 resin, or what is commonly termed "rosin." They are soluble in ether. 



Examples : Oleo-resin of capsicum, oleo-resin of aspidium. 



Resina, pi. resinae. — Resins are brittle, amorphous solids, soluble in 

 alcohol and alkalies. They are obtained from pleo-resins by simple dis- 

 tillation, as in the case of turpentine; or may be extracted from plants 

 by means of heat or alcohol. 



Examples : The resins of Burgundy pitch and podophyllmn. 



Balsamum, pi. halsama. — Balsams are oleo-resins with the addition 

 of either cinnamic or benzoic acids, or both. They are solids or liquids. 



Examples: Balsam of Peru, balsam of Tolu. 



Gummus, pi. gummi* — Gums are solid exudations from plants. 

 They are generally soluble in water, and their solutions are precipitated 

 by alcohol. 



Example: Gum acacia. 



Gum resina, pi. gum-resinae, are solid exudations from plants con- 

 sisting of a mixture of a gum and a resin. 



Pharmaceutical Processes. 



Many of the technical methods are those employed in chemistry, but 

 of those more especially used in pharmacy are the following: 



Processes op Mechanical Division. 



Slicing. — This prepares the drug for further reduction, and is the 

 first of all pharmaceutical processes. 



Bruising or Contusion. — Consists in breaking the drug by force, and 

 is usually performed with an iron mortar and pestle. 



Rasping or Filing. — For those drugs not easily reduced by the for- 

 mer process, as guaiac wood. 



Trituration-. — Performed with mortar and pestle. The effect pro- 

 duced where there is a circular motion, accompanied by pressure. ^ 



Grinding and Sifting. — In order to exhaust drugs some must be 

 ground and sifted to a finer powder than others. To accomplish this, 



*Gumml (indeclinable noun), often used for gum or gums. 



Digitized by Microsoft® 



