[ 57 ] 
the red hot Iron did not kindle the Spirits, pro- 
vided one were fure this would always be the Cafe ; 
and if the Experiment were repeated with thefam® 
Confequence a good many times, one would venture 
to fay, that the Heat of the Iron contributed no 
Power of inflaming to the Effluvia. 
My Tube I have ufed of late is not made of the 
fine Elint-Giafs, but fuch as common Wine'Glaffes 
are made of. 
I have got me a Tube made of common green Glafs s 
This is exceeding light, in Comparifon with others > 
and may be excited with double the Time and Pain 
required for the others, but yet not without warm- 
ing it at the Fire 5 though this feems powerful enough 
to attraft the Bunch of Threads, yet I am not able 
to kindle any Spirits with it. 
I have made thefe Trials, that I might be able to 
determine which kind of Glafs afforded the greatefi 
Quantity of Effluvia , or at leafl: the ftrongeft, as 
near as might be 5 which may not be altogether 
nnufeful to be known. 
Tour hnmble Servant , 
H. Miles. 
H 
XL 
