Liquid medicines are usually ordered to be administered in quantities familiar to the laity, as teaspoonful, tablespoonful, wineglassful, teacupful, glassful, etc. The prescriber bases his calculations on such equivalents as a teaspoonful being one fluidrachm, a tablespoon-ful being four fluidrachms, etc., as shown on page 331. As a matter of fact, there is a great variation in the size of these measures. The teaspoonful is probably the most uniform of any, yet they vary through a range of over a hundred per cent. and the shape is such that even this variation is increased in use. A spoon filled nearly to the top may not contain more than half the amount that could be measured into it. Dessertspoons vary in size to such an extent as to render their use inadvisable; the same applies to the wineglass. It is interesting to note the difference in a wineglassful of castor oil and a wineglassful of old port or Spanish sherry. The cup used by the coffee taker confined to one cup a day and the one used for measuring a disagreeable purgative water are very different vessels.

The medical attendant must either accustom himself to recognize spoons, glasses, etc., of the proper size and have them set aside for use in measuring medicines, or he must insist on graduated medicine glasses.

Graduated medicine glasses, if of the proper size and make, possess many advantages. They are not acted upon by the medicinal agent; they are easily cleaned; they are marked to hold correct amounts; there is less discrepancy in filling a glass to a mark than in filling a spoon to the top; there is less chance for waste in administering from a partly filled glass than from a full spoon.

The lesson in domestic measures was very forcibly impressed upon the author in ordering a concentrated antiseptic solution with directions to use one teaspoonful of the medicine to two tablespoon-fuls of water. The result was very distressing and it was found that the patient used a teaspoon holding about 90 minims for the medicine and a tablespoon holding about 120 minims for the water.