This section is from the book "Practical Materia Medica And Prescription Writing", by Oscar W. Bethea. Also available from Amazon: Practical Materia Medica and Prescription Writing.
Latin, Aqua Destillata (Gen., Aquae Destillatae)
Eng., Distilled Water. 1000 volumes of water are distilled. The first 100 volumes, which contain the volatile impurities, are rejected. The next 750 volumes constitutes Distilled Water (U. S. P.). The remaining water contains the non-volatile impurities and is rejected.
This should be the vehicle used in prescribing solutions of silver nitrate, potassium permanganate, corrosive mercuric chloride, boric acid, calcium chloride, lead acetate and subacetate, iron sulphate, zinc sulphate, tartar emetic, and it is usually desirable for simple solutions of alkaloidal salts. It is entirely unnecessary to make common use of distilled water. Such employment may be well attributed by the pharmacist to the ignorance of the prescriber.
 
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