(58S) 
I alfo wiflit for fome of the Glow mmf, with which I formerly 
made other Trills. For though I forgot nor, what optracion the 
withdrawing of the Air, by our Engine is wont to have upon h'- 
ving creatures, ysx that made me not forbear my wifti ^ not only 
becaufe of the different efFefil I have found the Engine to h ;ve oa 
^In[e6ts in refp^d of other Animals, but becaufe I am not of the 
opinion of thofe modern Writers^ who will have the Light of 
Glow tww depend altogether upon their Life, and end with ic. 
Bat being not likely by my wifhes to procure any new fubje(a to 
mike triils on, I thought ficatleaft to do what was in my power; 
snd accordingly (to gratifie ihem, who, Iprefumcd, would, if 
prefenc, propofe fuch a Trial) ciufed a piece of iron to be forged, 
whofe top was of chebignefs of aNutmcgs the reft being aftcmm, 
of an inch, or an inch and a half long, tor which we provided a 
little Candltftick of Tobacco-pipe-clay, which would not yield 
any fmoik tofiiland darken the Receiver. Then having heated 
the iroit red-hoc, and placed it in this Clay, fo that the round pare 
was clearly protuberant, we conveyed it into a JJ^^^/Wof white 
Glifj, which was fo placed as to keep the fides at as good a di- 
ftance, as vyecould,from the Iron^ leift the excefTive heat (hould 
( as we much feared it would) break the Glafs. Then fending a- 
way the Candles^and making the Room dark, we haftily pumped 
cue the Air, bu: could not perceive the withdrawing of it had any 
operation oa the glowing /r^?^. And the ugh it continued fliining 
long enough to give us opportunity to pump out and let in the 
Air three feveral times, yet we could nor obferve, that the ^ir 
had any manifeft operation one way or other. For though upon 
the withdrawing of the Air the Jr^»;? grew dimmer and dimmer, 
yttthat I attributed to the cooling of it : and the rather, b:caufe, 
having (to examine the conjedure) let in two or three times the 
Air, when the Receiver had been exhaufted, there appeared no 
manifeft iacreafe of Light upon the fudden admiffion of it, 
Experiment VOL 
f jl" A v!ng formerly in our Pbyftco-MechanichallE^^mmenHSi- 
"I bout dui .Sprhg of the Jir obferved, That the Air is thus 
iz: d. V thick o^, S&md.. chat a Body but faintly fouading, being 
placed 
