272 MATER i A MEDIC A AND THERAPEUTICS. 



In passing through the kidney, it appears to stimulate 

 the cells, at least in some subjects, and acts as a diuretic. 

 Citrate of caffein is thus a powerful, hut somewhat uncertain, 

 remedy in dropsy, whether cardiac or hepatic. It is best 

 given after, and then along with, a stimulant diuretic, such as 

 digitalis ; for a short time ; and in moderate doses. 



YALERIAKACE.E. 



Valerianae Radix VALERIAN ROOT. 

 dried root of Yaleriana officinalis. From 

 indigenous to and also cultivated in Bri 

 Collected in autumn, wild plants being preferred. 



Characters. A short yellowish- white rhizome, with nume- 

 rous fibrous roots about two or three inches long ; of a bitter 

 taste, and a penetrating odour, agreeable in the recent root, 

 becoming fetid by keeping ; yielding volatile oil and valerianic 

 acid when distilled with water. 



Substances resembling Valerian : Serpentary, Arnica, Vera- 

 trum Viride, known by odour. 



Composition. The active principles of valerian are a volatile 

 oil and valerianic acid. The oil consists of a terpen valerene, 

 Ci H l6 , and an oxygenated oil, baldrian camphor, Ci 2 H 2o O. 

 Valerianic acid, C 5 H 10 2 , occurs in a large number of other 

 plants, and in cod-liver oil ; and can be derived from fousel oil 

 (amylic alcohol, or valeryl-aldehyd), C 5 H 12 0, by oxydation. It 

 is a colourless oily fluid, with a powerful odour and acid 

 burning taste ; soluble in 30 parts of water, and freely in 

 alcohol and ether. 



Dose, in powder. 10 to 30 gr. 



Preparations. 



A. Of Valerian Hoot : 



1. Infusum Valerianse. 1 in 36. Dose, 1 to 2 fl.oz. 



2. Tinctura Valerianse. 1 in 8 of Proof Spirit. Dose, 1 to 2 



fl.dr. 



3. Tinctura Valerians? Ammoniata. 1 in 8 of Aromatic 



Spirit of Ammonia. Dose, ^ to 1 fl.dr. 



B. Containing Valerianic A.cid : 



SodsB Valerianas. Valerianate of Soda. NaC 5 H 9 2 . 



Source. Made by (1) distilling Amylic Alcohol with Sul- 

 phuric Acid and Bichromate of Potash; (2) saturating the 

 distillate with Liquor Sodae, evaporating, liquefying, and 



