The truth of this law of medicinal combination must be continually felt by the practitioner in the ordinary routine of his practice, viz. NARCOTICS will better fulfil the intention of allaying irritation and pain, when composed of several of such medicines in combination, than when they consist of any single one, even should the dose, in this latter case, be increased. See _Formulæ 3, 4, 5_. ANTISPASMODICS acquire increased efficacy by the application of the same principle. _Form. 20, 21, 22, 23, 24, 25_. BITTER TONICS are also thus exalted, see _Form. 39, 40, 41_. The beneficial effects, however, which arise from combinations of this kind will admit of a satisfactory explanation upon another principle; we may, for instance, consider them as medicines, differing from each other in their composition, and producing by their union an assemblage of bitter, astringent, and aromatic principles. AROMATIC and DIFFUSIBLE STIMULANTS. There are perhaps no remedies which receive greater mutual benefit be intermixture with each other, than the individuals which compose this class; for they not only thus acquire increased force and efficacy, but at the same time they lose much of their acrimony; if, for instance, any one spice, as the dried capsule of the _Capsicum_, be taken into the stomach, it will excite a sense of heat and pain; in like manner will a quantity of _Black Pepper_; but if an equivalent quantity of these two stimulants be given in combination with each other, no such sense of pain is produced, but, on the contrary, a pleasant warmth is experienced, and a genial glow felt over the whole body; and if a greater number of spices be joined together, the chance of pain and inflammation being produced is still farther diminished. The truth of this law is also strikingly illustrated, as Dr. Fordyce has observed, by that universal maxim in cookery, _never to employ one spice, if more can be procured_; the object, in this case, being to make the stomach bear a large quantity of food without nausea.[243] This same principle also finds an illustration of its importance, as it regards the class of stimulants, in the following preparations of our Pharmacopœia, viz. “_Pulvis Cinnamomi Compositus_; _Infusum Armoraciæ compositum_; _Infusum Aurantii Compositum_; _Spiritus Lavendulæ compositus_; _Tinctura Cinchonæ composita_; _Tinctura Valeriana Ammoniata_; and the _Confectio Opii_, the elegant and scientific substitute for the celebrated _Mithridate_ or _Theriaca_. The practitioner is also referred to _Form. 45, 47_, and to _Allii Radix_.”