[ ^2 ] 

 Xr. General Conjideratlons on Vcgeialle Extra^s. By 



C. pARMENTiKR. 



, [Concluded from p. 3S6 of our laft Volume.] 



Juices of Plants. 



J. O prepare thcfe juices, they recommend to colleil the 

 plants when they are in full vegetation, to clean them care- 

 fully, to pound them in a marble mortar, I0 prefs them in- 

 cloled in a hair bag, after having added to ihem a little water, 

 but only when they are either a little too aqueous or too mu- 

 cilaginous. 



All the fap-veflels of the plant, or others, are broken by 

 the aSion of the peftle ; all the liquids which they contained 

 flow off, together with the green fecula and the attenuated 

 remains of the vegetable. 



They recommend to purify the juices either by reft, or by 

 the heat of boiling water, or by means of the' while of an 

 egg, or by making them pafs through gray paper. 



The firft method is fit for the juices of fruits. 



The fecond may be employed for all the juices of herbs 

 deftined to make extracts. 



The third may be employed for all juices, infufions, or 

 deco£tions, that do not contain tannin. 



The fourth is neccfiary for all juices the virtues of which 

 exid chiefly in the volatile principles. 



It is preferred in pharmacy for magifterial juices, whether 

 they be volatile or not; the two vifcous juices excepted. 



]\[aceraUo!i' — Injujion — Dcco^hn. 



In maceration, the cold water is attra6led by the dry vege- 

 table fubllances : it introduces itfelf into them, fwcUs them 

 up, and renders fluid whatever is foluble. 



It has been found that maceration is fudicient to obtain 

 from quaffia, and even quinquina, the real active parts con- 

 tained in them. 



In infufion, caloric more abundant than in maceration 

 renders the water more penetrating, more adlive, and more 

 foK'ent ; it becomes charged with a much greater number 

 oi tlic principles of the vegetable. The preparers of mudi- 

 cines make ufe of it in prelerence for dry herbs and for leaves, 

 which, like (enna, for example, caimol bear ebullition vviih- 

 oui lofing their virtues. 



In deeodlion, \\\£. water faturated with caloric acquires a 

 jnucii greater energy : it penetrates in a more intimate man- 

 ner 



