phcQd inom Receher^ gtve a yet weaker found, wheruheAir 
was withdrawn from about it, then when the Receiver was full of 
Air : I prcfumcd, feme curious perfoniwculd, if they had been 
preferUj defire to have a trial made, whether or no a (kail piece 
of Shining Wood being fo included in the Receiver^ as that tfae 
Pumpiog out of the Air fliould have no injurious operation upon 
- thebodyofitjitsLight would upon the withdrawing of the Air 
be nianifeftly dimini(Tbt, And this I was the lefs backward to try, 
becaufe (not to mention the which the former Experi- 
ments ftiew there may be in fome cafes between jL^]?^^ and Air) 
it did not readily occurr to my memory, that by any manifeft Ex^ 
feriment (for I know, there are probabje Reafons to prove it) it 
appeared, that a Body more thin than Air will or can tranfmit 
Light, t% well as other di^^hmom mediums. And thofe modern 
Atomijls^ that think, there is in our exh^ufied Receiver very miny 
times more Vacmm than Bodj^ would, I prefumed, be glad to be 
fupplied with an Argument againft the Peripateticks, to (how. 
That the Motion of Bodies, viz, the Corpufcks of Light^ may 
be freely made in F4r/^<?5 and proceed without the affiftance of a 
Vehicle. 
Wherefore having Hermetically feak J up a fmall piece of shi- 
fting Wcod in a (lender Pipe, and placed it in a fmall Receiver^ that 
was likewife made of clear Glafs, we cxhaufted it of Air, and af- 
terwards let in again that, which we had excluded. But by nei- 
ther of the Operations could we perceive any fenfible decre- 
ment or increafe of the Light of the Wood, though by that very 
Obfervation it appeared^that theGlafs had been well fealed, fince 
otherwife the included Air would have got out of the Pipe into 
the Receiver^ and have left the Wood without Light. 
Experiment IX. 
IHad alfo a mind to try, both what degree of RmfaBion of the 
Air would deprive the Wood of its fplendourin fuch and fuch 
meafuies, aqd whether or no the felf-fame Air, which, when rati- 
fied, would not fufferthe Wood to (bine, would, when reduced 
to its former denfity, allow it to fliineas much as before. 
This Ipropofed to do by putting fome Shining Wood into a 
Q^q clear 
