05 8 ?) 
placed in our Receiver, gave a yec weakei? found, when the Air 
was withdrawn from about it, then when the Receiver was full of 
Air : I prefumed, fome curious psrfons wculd, if they had been 
prefent, defire to have a trial made, whether or no a (kail piece 
of Shining Wood being fo included in the Receiver, as that the 
Pumping out of the Airfhould have no injurious operation upon 
the body of it, its Light would upon the withdrawing of the Air , 
be manifeftiy diminiiht. And this I was the lefs backward to try, 
becaufe (not to mention the Relation , which the former Experi- 
ments (hew there may be in fome cafes between Light and Air) 
it did not readily occurr to my memory, that by any manifefl Ex- 
periment (for I know, there are probable Reafons to prove it) it 
appeared, th t a Body more thin than Air will or can tranfinit 
Light, as well as other diaphanous medium s. And thofe modern 
Atomijls 3 that think, there is in our exhattfied Receiver very mmy 
times more Vacuum Bod^ would, I prefumed, be glad to be 
fupplied with an Argument againft the Peripatcticks, to (how. 
That the Motion of Bodies, viz. the Corpufcles of Light, may 
be freely made in Facuo 0 and proceed without the affiftance of a 
Vehicle. 
Wherefore having Hermetically feale Jupafmallpiece of shi- 
ning Wood in a (lender Pipe, and placed it in a fmill Receiver , that 
was likewife made of clear Glafs, we exhaufted 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 fenfibie decre- 
ment or increafe of the Light of the Wood, though by that very 
Obfirvation it appeared, that the Glafs had been well fealed, fince 
otherwife the included Air would have got out of the Pipe into 
the R€ceiver y m& have left the Wood without Light, 
Experiment IX. 
I Had alfo a mind to try, both what degree of Rarefaction of the 
Air would deprive the Wood of its fplendourin fuch and fuch 
meafures, and whether or no the felf-fame Air, which, when rati- 
fied, would not fufifer the Wood to {hine, would, when reduced 
to its former denfity, allow it to fhiaeas much as before. 
This Ipropcfed to do by putting fome Shining Wood into a 
Qiiq “ clear 
