[ 33 8 1 
Exf. 53. Laftly, I heated the done again, and, 
whilft it was red-hot, I threw it into water ; by which 
treatment the virtue of the Tourmalin was mtirely de- 
stroyed, and it had the appearance of being fhivered 
in many parts, without breaking. 
IN regard to the internal frame of the Tourmalin,, 
we can fay nothing ; yet fo much I have learned, by 
thefe experiments, that there are three different me- 
thods of heating the Tourmalin , which produce dif- 
ferent eledtric appearances ; that different degrees of 
Wat, afford different appearances ; that friction has 
the fame effedt upon it, as upon glafs ; and that the 
Tourmalin , when it is heated properly, fufters a cur- 
rent of the eledtric fluid to pafs through it in one di- 
rection only : fo that the Tourmalin hath, as it were, 
two electrical poles , which are not eafy to be deffroyed 
or altered ; and farther, that there is not any fubflance 
in nature , which we are acquainted with , that the 
eleClric fluid does not readily pafs through ; that there 
feems to be a conflant flux and reflux of it in all bodies , 
as well in the air as in vacuo, occafioned by the alter- 
nate changes of heat and cold in every part of this globe- 
All which things do very much confirm the opinion 
I formerly entertained, and attempted to prove by 
experiment, that the eleClric fluid is diflufed through- 
out the whole earth , as well as in the air furrounding 
it *. 
How far this fW/ing of the eledtric fluid may be 
concerned in the ordinary operations of nature , by 
keeping up that motion, which feems fo neceffary in 
the feveral parts of the grand machine , I leave to others, 
who may be more fuccefsful in their lefearches. 
* See a Treatife on Eleadcity, the ad Edit, by B. Wilfon. 
