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Elements of Pharmacy.

part I.

qualities, possess great brilliancy or lustre from their powerof reflecting almost all the light which falls upon their sui--face. Their colours are generally shades of white, gray, oryellow; their hardness is considerable, and according to itsdegree they are more or less elastic : one only, mercury, isin a fluid state at the ordinary heat of the air. Many ofthem possess considerable tenacity, and are consequentlymalleable and ductile; but some are extremely brittle.Metals are sapid and odorous when heated or rubbed ; theirfracture is generally hackly; their texture fibrous or foliated;and many of them are sonorous. They are excellent con-ductors of caloric, electricity, and galvanism. When ex-posed to the action of caloric, they expand and are melted ;but differ greatly with regard to fusibility; some of themare volatilized at known temperatures. When fused, theirsurface is convex and globular; and in cooling they general-ly crystallize. They are very susceptible of oxidizement.The following metals are used as pharmaceutical agents.

I. Malleable.

1.%

3.*.

Silver. (See Part ii.) 5. Tin. [Part ii.)Mercury. (Ibid.) 6. Lead. (Ibid.)Copper. (Ibid.) 7. Zinc. (Ibid.)Iron. (Ibid.)

II. Brittle and easily fused.

1. Bismuth, a reddish white coloured brittle metal of a lamel-lar texture. Its specific gravity is 9'S22, but this is increasedby hammering. It fuses at 476° Fah. and crystallizescooling : in a higher temperature it volatilizes unaltered ;and on the access of air burns with a blue flame, emittinga yellow smoke, which is an oxide of the metal. Themineral acids act on it; and it readily combines with sulphurand most of the other metals.

2. Antimony. (Part ii.)

3. Arsenic. (Ibid.)

III. Brittle and difficultly fused.

1. Manganese. (Part ii.)

Boron is obtained from the decomposition of boracic acid, inthe form of powder, of a deep olive colour, insipid, inodorous,and insoluble in water. It undergoes no change at any tem-perature, when heated in close vessels ; but takes fire andburns like charcoal, when heated in the air to about 600°.During combustion it attracts oxygen, and is converted intoboracic acid. It is also converted into the acid by decom-posing sulphuric and nitric acids when it is treated withthem. It combines with the alkalies and sulphur.

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