126 PHILOSOPHICAL TRANSACTIONS. f ANNO 1 696-7. 



the very kind with the cominon sorrels and lapathums, he beheves it not im- 

 possible, even from our own store, but herb-gums might in some way be had. 

 It exudes from all parts of the stalk and ribs, on the underside of the leaf it- 

 self. He gathered some in the form of good large drops; others, as though 

 the stalk had been besmeared with it ; others, shot into long and twisted wires 

 or icicles. He observed, that the cankered orifices, or places where the gum 

 had burst out, might be followed into the stalk with a knife, and that through 

 the skin : in certain places it could be seen that the juice within the plant was 

 turned gummy, and looked clear like ice. 



The juice extracted from the roots of our English rhubarb, by a tincture of 

 fair water steamed away, is nothing else but a lean unintlainmable gum ; and 

 though it differ in colour from the exuding gum ; yet in other natures, as this 

 of being uninflammable, ductile in the flame ot a candle, he. it agrees with it. 



We may here give a probable reason, why a gentle infusion or maceration of 

 rhubarb, is a very sure purge, but the substance or powder, or a decoction of 

 it, will have a quite contrary effect, and bind. We may, I say, think, that the 

 sharp and tart juice in rhubarb, wherein its purging faculty lies, is by a gentle 

 infusion so extracted, that it turns not to gum in the stomach. For it cannot 

 be thought that the sour juice of rhubarb is a distinct liquor from the gum, 

 which seems to be only an accidental coagulation. 



Lauro-cerasus, a beautiful winter green, which we have adopted to adorn our 

 court walls with, yields a clear gum very plentifully: it is very white, and 

 very clear. 



There are other sorts of juices, which will not of themselves exude out of 

 the wounds of their respective plants ; and of this sort of plants is the holly. 

 He wounded the holly the latter end of March ; and yet after some days of 

 warm and open weather, he could not perceive the least stirring of juice. The 

 latter end of May, the bark begins to be full of lime, which may be tried by 

 pressing a piece of it between the fingers; when you would take them off, the 

 juice or lime draws out into hairs, and follows the fingers, cleaving to them like 

 small threads. This lime or juice is separated from the bark thus: peel off the 

 bark in the months of May, June, or July; for it then comes easily away, and 

 most abounds with juice: boil the bark in fair water, until it be so tender, that 

 the outmost thin grey bark or membrane peels easily off; lay it so peeled, and 

 cover it over with green nettles or fern, or such like, in a cellar for about ten 

 days, where it will ferment or rot, and become mouldy. Take them out, and 

 beat them well in a mortar to a paste, and roll them up into small hand-balls, 

 and in a running spring wash them clean, from all the woody or sticky parts; 

 which is effected by drawing and teazing them. But great care is to be taken 

 in the washing of the balls ; for besides that they must, if possible, be forth- 



