being well known that the action of drugs varies greatly with the size of the dose, small doses in their action being often directly opposite to large doses.

Ordinarily, it is unwise to prescribe medicines to be dropped out, since a drop varies greatly in dimension according to the viscosity and specific gravity of the fluid, the shape, size, and character of the neck and lip of the bottle, as well as its degree of fulness, and the steadiness of the hand in dropping.

In computing doses of powerful medicines, therefore, always estimate for minims instead of drops.

Direct the use of a "dropper" or minim pipette for the administration of liquids by drop doses, such as Fowler's solution, collyria, etc. There are exactly sixty minims of any fluid to one fluidrachm, while sixty drops may be fewer or more than one drachm, as the following list shows:

LANGUAGE AND GRAMMATICAL CONSTRUCTION OF PRESCRIPTIONS.

A prescription is written partly in Latin, partly in English. The name of the patient and the date should be in English; the superscription in Latin abbreviations; the inscription in Latin; the sub

scription in Latin or Latin abbreviations; and the signature, or directions to the patient, in English.

A prescription properly and unmistakably written is a cardinal requisite to the successful administration of medicine, no less than to its correct preparation by the druggist. Every practitioner and pharmacist should possess some knowledge of Latin grammar, yet by the observance of a few simple rules one wholly ignorant of the language may acquire a proper use of the forms generally adopted; and a little study, aided by constant practice, will soon fix in the memory the peculiarities of gender, case, and number, together with the agreement of adjectives, to be met with in all prescriptions.

It is to be observed that the Latin tongue has been chosen as the medium of medical and pharmaceutical instructions because of its conciseness, stability, and universal acceptance by the scientific world. Moreover, the Latin name is specific, while the English name may refer to several drugs of entirely different properties: for instance, "Snake root," applied by residents of this or that locality to Cimicifuga racemosa, Aristolochia serpentaria, Asarum Canadense, Eupatorium aromaticum, Polygala Senega, etc.

To begin with, then, the prescription-writer must endeavor to lay aside English and familiarize himself with various Latin verbs (most of them in the imperative, or commanding, mood); a long list of drugs and medicines, to be correctly written and pronounced; a limited number of adjectives, agreeing in gender, case, and number with the nouns they qualify; a few prepositions governing certain fixed cases; and a small number of terms and phrases of general importance. Let us consider them seriatim.

VERBS.

The first item of a prescription is a verb: recipe, "take," the sign being R. One need not know the conjugation of the Latin recipere to understand the import of this order. Such imperatives simply signify the instructions of the physician.

A very few verbs are used in the subjunctive mood, having the force of the imperative, such as fiat, pl. fiant, "let it, or them, be made (into, in pilulas); or "letbe made," as in the expression fiat mistūra, “let a mixture be made"; sufficiat, “may suffice," as in the common instruction, abbreviated "q. s.," quantum sufficiat, “as much as may be required"; ne repetātur, “ do not let it be repeated," or "do not repeat"; bulliat, "let it boil."

A future passive participle is also frequently used: dividendus, like an adjective agreeing with the noun in gender, case, and number, and signifying "to be divided (into)," as in the order in trochiscos dividenda (măssa), “to be divided into troches," though the imperative divide, "divide into," is often used.

NOUNS.

These form by far the largest vocabulary, including all official and nearly all unofficial drugs and medicines, together with their compounds. A considerable number, ending in a, are of the first declension, all feminine.' Example:

[The Latin dative and vocative cases are never used, and the plural number rarely.] An extensive list of medical agents ends in us (generally masculine) or um, on (neuter), and are of the second declension. (Prīnos, masc., is exceptional.) Example:

The genders of nouns are given as a guide to the agreement of adjectives.

It may be noted, in passing, that the genitive singular is almost exclusively used in prescription-writing.

We are now prepared to analyze a simple prescription and understand its elements.

Referring to the foregoing examples, suppose we wish the druggist to supply three drachms of olive oil. We prescribe as follows:

It must be borne in mind that the direct object of the imperative recipe in this example, as well as in all similar cases, is not the medicine ōleum, but the amount of it prescribed, as indicated by the Roman numerals and the symbol of Apothecaries' weight, which, written in full, would be tris drachmas (acc.). In this class of prescriptions, therefore, including nearly all in use, we need consider only the genitive, the accusative or grammatical object of the verb being expressed in the quantity symbolically indicated.

It will be noted, moreover, that the construction, or order, of the Latin words is the reverse of English usage. Yet it is evident that a grocer's clerk, for instance, might well, and frequently does, employ the same mode of expression:

(of) Granulated Sugar Ibs 10

a construction precisely analogous to that of the above prescription, which simple form may be taken as a type for all, subject to such modifications as the nature of the drug and the treatment may require.

Nouns of the second declension ending in on, all neuter, are of Greek derivation, and are declined like oleum. Example:

The remaining nouns of the second declension all end in us

(with four exceptions, masculine), and are declined like the following example:

Indeed, all prescription nouns ending in us are of the second declension, save seven:

The four exceptions to the masculine gender mentioned are:

With these to be committed to memory-the second declension ends, so far as it concerns the prescription-writer.

While touching upon the fourth declension it may be well to complete the study of it, there being but six nouns, ending in us, of this declension (Rhus is of the third). They are, as already enumerated: