1 46 Of the Advancement of Learning. L i b. V, 



the makjtfg of Paper is only tried in linen, and not in (ilk, (unle(s per- 

 chance amongft the Chinefes -j nor yet in ftufFs intermixt with hair and 

 briftles, of which is made that which we call chame-Iot^ nor yet ia 

 woollen, cotton, and skins, although thefc three lafl: feem to be more 

 Heterogeneous, and Co rather may become ufeful mingled, than (epa- 

 rate : So infition in fruit-Trees, is pradis'd, but rarely tried in Trees 

 wild 5 although it is affirm'd that an Elm grafted upon an Elm, will 

 produce wonderful (hades of leaves. Infition likewife in flowers, is 

 very rare, though now the Experiment begins to be made upon musk- 

 Roies, which are fuccefsfuUy inoculate upon common R.ofes. So we 

 place the variation in the Tart of a thing amongfi the variations in Alat" 

 ter. For we fee a fcion, or young flip grafted upon the trunk of a tree, 

 to (hoot forth more profperoufly, than if it had been fet in earth: And 

 why, in like manner, (hould not the feed of an Onion inferred into 

 the head of another Onion while it is green, germinate more happily 

 than if it had been fown in the bare earth ? And here the Root is vari- 

 ed for the Tr/m^s that the thing may feem to be a kind of infition ia 

 the root. Secondly^ the variation of an Experiment may be made in the 

 efficient. The beams of the Sun through burning-Gla(ies are (b fortifi- 

 ed, andintended to fuch a degreeofheat, that they are able to (et on 

 flame any matter, which is apt eafily to conceive fire : Now whether 

 may the beams of the Moon^ by the fame GlafTes be aftuated by fome weak 

 degrees of warmth 5 that we may fee whether all heavenly Bodies be 

 hot in power ?^o bright and radiant heats are exalted by GlafTes ; Whe- 

 ther are gloomy and opaque heats (as of ftones and mettals, before they 

 be made burning hot by the force of fire) fubjeft to the fame impreffi- 

 on , or are they rather in this fbme portions of light? So Amber, and 

 Jet, or an Aggat chafed draw unto them ftraw 5 whether warmed 

 at the fire will they do the like ? Thirdly, the variation of an Expe- 

 riment may be made in ^antity, concerning which a very diligent care 

 is to betaken,being it is encompaffed with many errors. For men are 

 of opinion //^^^ if the Quantity be augmented and multiplied^ the virtue 

 is proportionally augmented and multiplied'^ and this commonly is with 

 them a Poftulatum, and a fuppofed truth, as if the matter were a Ma- 

 thematical certitude 5 which is utterly untrue. A globe of Lead, or a. 

 pound in weight let fall from a Tower, fay, it defcends to the earth in 

 the fpace often Pulfes 5 whether will a Globe of twopottnd weight (in 

 which that force of Motion, which they call Natural, (hould be doubl- 

 ed,) light upon the earth in the fpace of five Pulfes? But that Globe 

 (hall come downalmoft in an equal fpace of time with this, and fhall 

 not be accelerated according to the meafure of^antity. So (ima- 

 gine,) one dragm of Sulphur mingled with half a pound of Steel, it 

 will make it fluid and liquid •-, Will therefore an ounce of Sulphur fuffice 

 to thediffolvingof four pounds of Steel? But that follows not 5 For 

 it is certain that the objiinacy of the matter in the Patient is more encreas'd 

 by^antity, than the A3ivity of the virtue in the Agent. Befides, too 

 much, as well as too little fruftrates the efTefl: : For in the excodtions 

 and depurations of Mettals it is a fimiliar error, that to advance exco- 

 ftion, they augment the heat of the Furnace, or the ^antity of the 

 InjeUion ^ but if thefe exceed due proportion, they hinder the opera- 

 tion 3 becaufe through their force and acrimony, they turn much of 



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