TONICS. 45 



rhubarb and aloes, in the constipation of old persons, and as an 

 emmenagogue. Advantageously given to children by enema, in 

 which case it will often prove laxative. 



Dose of substance, gr. v to 9j, given in form of pill ; of the 

 emulsion, {Lac assafcEtidce), f 3ss. to fjj ; of the tincture, f 3j. 



AssafcBtida is sometimes used in the form of a plaster, in chronic 

 swellings. 



Valerian. — (Valeriana, U. S.) 



Root of the Valeriana officinalis^ a perennial plant, indigenous in 

 Europe, growing about two or three feet high. The root consists of 

 a short tuberculated rhizome, from which issue numerous round, 

 tapering fibres, of a yellowish-brown colour externally, and whitish 

 internally. Taste, bitter and acrid ; odour, when dry, strong, pecu- 

 liar, and somewhat aromatic. It depends for its virtues on a yellow 

 volatile oil, separable by distillation, and an acid, named valerianic 

 acid. 



Uses. — A mild antispasmodic and stimulant. Useful in hemi- 

 crania, combined with cinchona ; also in slight nervous derange- 

 ments. Best given in form of infusion, made with half an ounce 

 of the root to a pint of boiling water; dose f3i to fjij. Dose of 

 the oil of valerian, 3 to 5 drops. 



Garlic — {Allium, IT. S.), is decidedly antispasmodic, especially 

 in cases of children, to whom it may be advantageously applied in 

 the form of cataplasms to the feet, to quiet the nervous irritation to 

 which they are frequently liable in the course of disease. Some- 

 times employed as a counter-irritant to the spine, in cases of hooping- 

 cough. It is likewise expectorant. 



CLASS III. — TONICS. 



Tonics are medicines possessing the power of gradually increas- 

 ing the tone of the muscular fibre, when relaxed, and the vigour of 

 the body when weakened by disease. Though resembling astrin- 

 gents in some of their effects, they do not produce corrugation, ex- 

 cept when combined with the astringent principle. They resemble 

 the stimulants in the fact of acting on the system through the 

 medium of the nervous system ; but they differ from these in the 

 slowness, as well as the permanency of their effects. Carried to 

 excess, they are productive of debility ; and if used in a state of 

 health, they act injuriously, causing an excitation, followed by a 

 proportionate degree of debility. Tonics are particularly indicated 

 in functional disorders of the digestive organs, as dyspepsia, and in 

 the convalescence from acute disorders. Bitterness was at one time 

 supposed to be an essential condition to constitute any remedy a 

 tonic ; and although it is true that nearly, if not quite all, the vege- 

 table tonics have a bitter taste, still the fact that the mineral tonics 



