I took a piece of Leaf Brafs, and laid it between two 
pieces ot Wood about an Inch in thickntfs, and the fame 
dihance afunder* Then lapply’da well rubb’d Tube to 
attradt the Brafs, evenfo near as the Wood would lufFer, 
but gave it no manner of Motion 3 but fo foon as the 
Wood was remov’d, and the Coutimum of its Sphere re- 
ftor’d, the Brafs was driven to it very vigoroufly, with- 
out any frelh Attrition ^ which I think moft plainly proves, 
that the Adtion of the Effluvia^ or at leaft in a great mea- 
fure, is loft, if the Parts of it are difcontinu’d by any 
thing Interpofing, or Interrupting its Spherical Figure. 
Nay, I have try’d, by holding the Tube fo, that its 
Sphere might meet with no Interruption by the Wood in 
its Circle round the Axis of the Glafs, yet this would 
exhibit nothing neither 3 by which I find, that if the 
Parts of the Effluvia are in a manner interrupted, their 
Adtion is loft, or at leaft mightily impair’d. 
