86 
ON FLUID EXTRACT OP VALERIAN. 
tance, and of all that reaches our market the fresh English 
is decidedly to be preferred. The whole operation should 
be conducted with all those precautions so necessary in the 
proper management of displacement. 
The proportions I have adopted are as follows : 
Rad. Valerian, offic. gviij. Troy. 
Spt. Vim Rect. f.lviij. 
Ether. Sulph. fjiv. 
Aquae q.s. 
Having finely bruised the root, place it in the instrument. 
As the alcohol and ether do not interfere in their action, 
mix and obtain by careful percolation as strong a tincture 
as can be made, which may be determined by the liquid 
ceasing to acquire additional colour or taste; remove the 
last portions by water, and set the solution aside in an open 
dish in a warm room to evaporate, which it is allowed to 
do until all the ether and half of the alcohol are gone. The 
remainder then amounts to f.jiv., is of a greenish colour, 
oily, containing all the acid, consequently having, in a high 
degree, the well known taste and odour of the root. 
We then proceed with water, and if the first portion 
is mixed with any of the preceding menstruum, it should 
be submitted to gentle heat in order to expel it. The 
first fjviij.of cold infusion free from spirit are set aside, 
because if any of the volatile principles which may be left 
in the root are soluble in cold water, they will be taken up, 
and the concentration may be practised on the remainder 
without danger to the extractive. The root is finally ex- 
hausted with cold water, which is to be determined mainly 
by the taste ; the colouring principle, continuing, as in the 
case of Krameria, after all the bitternesses extracted. Evapo- 
rate this by a water bath or steam-heat to f.^iv.,and finally 
mix all these solutions, and if a slight turbidness be observ- 
able, which has always been with me very trifling, it may 
be readily clarified by passing a few times through some 
of the exhausted dregs left in the displacement filter. 
