What are the conditions required of a well-made pill? This was a question asked in the original treatise by Mr. A. W. Gerrard, then head dispenser at University College Hospital, London. He answered it as follows:

(1)The ingredients of which it is composed should be worked into an intimate admixture, no individual particles being discernible.

(2) The parts should be held together by some cohesive force, sufficient to withstand the process of rolling and cutting without undergoing crumbling or cracking.

(3) The pills being formed should retain under ordinary conditions a perfectly globular form.

(4) The excipient, whether indicated by the prescriber or left to the discretion of the dispenser, should be chemically and therapeutically compatible with the other ingredients.

(5) The pills should disintegrate readily soon after ingestion. Failure to produce these conditions may be ascribed to a variety of causes-as, for example, excess or deficiency of a moist extract; presence of hygroscopic or deliquescent bodies; chemical incompatibility of ingredients; excess of essential or fixed oils; injudicious choice and use of exci-pients, or bad manipulation.

The following are some prescriptions illustrating cases of failure, and the means of overcoming it:

Fiat pilula.

Pills made from these ingredients soon lose their round form, becoming moist and unsightly; the addition of 1/2 grain of tragacanth powder sets all right, by absorbing moisture and imparting solidity.

Fiat pil. Mane et nocte sumend.

This pill has the same defects as the previous one, but the materials of each pill, 5 1/2 grains, make it too bulky to risk an addition. The difficulty can be got over by drying the extract of henbane on a pill-tile over a water-bath. Bear in mind volatile bodies must not be so treated.

Fiat pil. Sumend. ante cibum.

Of all masses this is one of the most obstinate and vexing, as it becomes rapidly tough and unmanageable, owing to the silver oxide being slowly reduced. A small admixture of confection of hips with the oxide at starting generally gives a good result.

Fiat pil.

Here essential oil is in excess, and the ingredients refuse to form a tenacious mass. In such a case the addition of 1/2 grain of soap per pill brings them under control. Soap should not be used for salts of iron, lead, bismuth, copper, or mercury, as oleates would be formed.

Olei crotonis ....... mj.

Fiat pilula. Statim sumenda.

For this pill nothing is better than 2 grains of compound tragacanth powder and 1 grain of soap. This excipient subdues croton oil perfectly, and it is equally suitable for creosote and carbolic acid.

Compound tragacanth powder is about the best general pill-excipient. The simplicity of its constituents admirably adapts it as a diluent of all substances given in small doses; whilst under its influence, in the presence of a little water, the most obstinate ingredients are brought under control. Solubility with easy disintegration is another of its characteristics. When oils have to be dealt with, a little soap may be added to the compound tragacanth powder with advantage.