PREPARATION OF THE JUICE OF DANDELION. 
65 
roots and herb loses its bitterness by long boiling, and that it even 
assumes a saline sweetish taste, such as is observable when it is 
extracted from plants dug during the cold months of # the year. 
The change happens more easily in the juice of the leaves than 
in that of the roots ; yet a decoction of the roots long boiled re- 
tains but little of its bitterness. The recent juice of the roots, if 
evaporated to dryness and restored to its original bulk by the ad- 
dition of water, will be found by far less bitter than before. The 
solid extract is therefore a bad preparation, and as Lewis observes 
becomes worse still by being kept. Indeed the extract of com- 
merce has but little bitterness, and is often so sweet as to sug- 
gest a suspicion that it contains a foreign admixture : I have 
sometimes thought that it was the sweetness of Spanish liquorice. 
Its color, which ought to be brown, is generally black. 
" The bitterness is due to the presence of a proximate principle 
said to becrystallizable. When this has been impaired or removed 
by boiling, a sweetish, saline, and even acidulous taste is discovera- 
ble : it naturally belongs to the juice ; for, besides the bitter principle, 
it is known to contain phosphates, sulphates, muriates, and tar- 
taric acid, or a bitartrate, which are the useful ingredients : along 
with uncrystallizable sugar, gum, inulin, caoutchouc, and some other 
matters of no medicinal importance. The bitter principle and salts 
are the constituent ingredients which claim the attention of the 
practitioner ; and it is to their preservation, by whatever process 
the juice is prepared, that the apothecary should devote his atten- 
tion ; for, as Dr. A. T. Thomson truly observes, ' much depends 
on the nature of the preparation.' 
" Keeping the foregoing observations in view, the best mode of 
conservation is obvious. The whole herb as soon as dug is to be 
washed immediately, well pounded, and the juice extracted by 
means of the press. Delay in pounding the roots will soon begin 
to impair their bitterness ; and even the expressed juice will speed- 
ily begin to change unless put in process of preservation very 
soon after expression. When the juice has been pressed out, the 
marc, still containing valuable matter, is to be well mixed with as 
much water at 200° as will bring the whole to about the consistence 
of a pulp. After standing two hours, the liquor is to be pressed 
out, added to the former product, and the mixture is to be very 
slowly evaporated in a wide earthen vessel, with constant agitation, 
6* 
