paration is relatively of no importance: the numeral two indicates roughly 

 a preparation of an importance mid-way between the other two. It will 

 be noted that drugs of the fourth class have as a rule preparations without 

 a numeral prefix In some cases none of the preparations of a drug seemed 

 worthy of the numeral one or even of the numeral two, this indicates that 

 the drug is much more important than any of its preparations. 



The official Latin name of the drug is always given; its English equiva- 

 lent only when difficulty might arise in translating the Latin or where 

 other considerations seemed to render the giving of it an advantage. Im- 

 portant synonyms are in many case also given: they are always enclosed 

 in brackets. The dose is given in both the Imperial and the Metric 

 systems. The Imperial as being the official dose is given the preference. 

 The doses in the Metric system are as a rule those of the British Pharmaceu- 

 tical Codex, though the term "mil" and its diminutives in spite of its 

 very obvious advantages have not been adopted. Doses enclosed in brackets 

 are not official. 



No attempt is made to give the full Pharmacopreial definition of 

 any drug or description of its physical or chemical characters, enough only 

 is given to draw the attention of the student to some of its outstanding 

 characters a knowledge of which may be of advantage to him. The for- 

 mulae for the preparation of galenicals are as a rule taken from the British 

 Pharmaceutical Codex. In this the Pharmacopceial formulae have been 

 recalculated so that the total of the quantities of the ingredients at the 

 end of the process of preparation will aggregate 100. The advantages of 

 this centesimal system are obvious, the principle one, being the ease with 

 which the percentage strength of any ingredient may be seen. It is an 

 added advantage in a laboratory where the dispensing is carried out in the 

 Metric system. No attempt has been made to give a detailed description 

 of the steps to be pursued in the preparation of any galenical, but only 

 enough is indicated to aid the student to use them intelligently in dis- 

 pensing and prescribing. For a knowledge of the steps in preparation of 

 galenicals the student is referred to the Pharmacopoeia or the Codex. 

 Where the formula of any preparation is given the first quantity preceeded 

 by a dash indicates the quantity of the drug or preparation under which 

 the preparation in question is classed. 



The more important solubilities of the drugs are also given and are 

 stated for room-temperature, 15.5 C, unless the word "hot" is used as 

 meaning boiling (by cold is meant 15.5 C as opposed to boiling). Solu- 

 bilities are always expressed in parts by weight. By water, distilled 

 water is always meant and by alcohol, 90% alcohol (Rectified Spirit). 



The important incompatibilities are given with often an indication of 

 the chemical change occuring. In some cases methods of overcoming or 

 lessening the incompatibility are also given. 



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