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one next, and the others in Order fucceffively to the 
red one, which was attracted leaf!, and the laft of 
them all. I afterwards cut out nine fquare Pieces of 
Gaufe, of the fame Colours with the Ribbons, and 
having put them one after another on a Hoop of Wood 
with Leaf-Gold under them, the Leaf-Gold was at- 
tracted thro’ all the coloured Pieces of Gaufe, but 
not thro’ the white or black. This inclined me at 
firft to. think, that the Colours contributed much to 
Ele&ricity. But three Experiments convinced me of 
the contrary : The firft, that by warming the Pieces 
of Gaufe, neither the black nor white Pieces obftruCl- 
ed the Aftion of the Eledrical Tube more than thofc 
of the other Colours. In like manner, the Ribbons be- 
ing warm’d, the black and white are not more ftrong- 
ly attracted than the reft. The fecond is, the Gaufes 
and Ribbons being wetted, the Ribbons are all at- 
tracted equally, and all the Pieces of Gaufe equally 
intercept the A&ion of Eledrick Bodies. The third 
is, that the Colours of a Priftn being thrown on a 
Piece of white Gaufe, there appear no Differences of 
AttraCfion. Whence it follows, that this Difference 
proceeds not from the Colour, as a Colour, but from 
the Subftances that are employ'd in the dying. For 
when I coloured Ribbons, by rubbing them with 
Charcoal, Carmine, and fuch other Subftances, the 
Differences no longer proved the fame. 
Fourthly, Having communicated the EleCtricity of 
the Tube by means of a Packthread, after Mr. Grayh 
manner, I obferv'd, that the Experiment fucceeded 
the better for wetting the Line ; and that it may be 
fupported on Glafs-Tubes inftead of Silk-Lines. 
And I made this Experiment at iz$6 Feet Di fiance, 
in 
