194 MEM OIKS of the 
maceration of rhubarb is a very fure purge, but the fubftancc 
or powcicr of rhubarb, or a decoaion thereof, will have a quite 
contrary eftlcl. and bind 5 the fharp and tart juice m rhubarb, 
wherein its purging quality lies, is by a gentle infufiop fo 
cxtra6ied, that it turns not to gum in our Itomachs. 
Green plumbs and floes do often exfudate a gum, which is 
dear and tranfparent. Lauro-cerafus, a beautiful winter- 
oreen, which we have adopted to adorn our court-walls with, 
yields a clear gum very plentifully 3 it is very white, and very 
clear« 
Dr. Lifter wrenched and wounded the holly, the latter end 
c{ March, and yet after fome days of warm and open weather, 
he could not perceive the lead flirring of juice j the latter end 
o{May\ the bark begins to be full of lime or Itringy juice, 
which you may try by preffing a piece of it betwixt the fingers, 
and when you would take them oft; the juice or lime draws out 
into hairs; this lime is feparated from, or taken out of the 
bark thus 3 peel off the bark in May, June, or July, for^hen 
it comes ealilv away, and moil abounds in juice 5 boil the 
bark in fair water, till it be fo tender, that the outmoft thin 
jrrey bark or membrane, will peel off eafily 5 lay it fo peeled, 
and cover it over with green netdes, fern, or luch like, m 
layers, in a cellar for about ten days, where it will ferment or 
rot, and become mouldy 5 take them out, and beat them well 
in a mortar to a pafte, and roll them up into fmall hand-balls, 
and in a running fpring wafh them clean from all the woody 
parts, which is'done by pulling and teazing them. In cutting 
fhe tender tops of elder, the latter end of May, there will run 
out a ftringy juice, fomewhat like bird-lime, or the juice of 
holly 5 it feems to be contained in certain veins, juft within the 
circle of teeth or wood. . 
The diffec^ed veins of many plants afford an oil, that is, 
fuchajuice, which, being rubbed between the fingers, is not^ 
at all clammy, but makes them greafy 3 you may take of^ 
u'ith a clean knife the juice o^ Helen turn oxEnula campana, J.B. 
and it looks like oil mixed with watery the fame experiment 
may be made on Gcutaj the juice 01 Jl!ig;ellc<i Sativa, Park, 
after a few years keeping was grown very limy. If m j^^f'^ 
you drip off the leaves of 'Tapfus barbatus, Ger. it feems to 
yield an oily juice, but much diluted with water; it Iprings 
freely and enough, is of a dark green colour. The fruits of many 
plants afford oil, as olives, the^terries of laurel, ivy, juniper, 
female cornel, or dog-tree, ^c. The pulp of moft Iceds feem 
