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after giving them many candid Trials, I cannot think 
them equal to their Recommendation. I firft tried 
one of them in a fmart Shower of Rain after a dry 
Day, when the Drops were large, and the Spirit fired 
three times in about four Minutes : The fame Effect 
fucceeded, under the fame Circumftances, from the 
white one; but, after three or four Hours raining, 
when the Air was perfectly wet, I never could make 
it fuccecd. And, to illufirate this Matter further, I 
have been able, when the Weather has been very dry, 
with once rubbing my Hand down this blue Tube, 
and applying it to the End of an iron Rod fix Feet 
long, to throw off fevcral Pieces of Leaf-Silver lying 
upon a Card at the other End of this Rod j whereas 
I never have been able to throw it off by any means 
in very wet Weather. Befides, I am of Opinion, 
thar, after the electrical Fire is gone from the Tube, 
the Tube has no Share in the conducting of it: My 
Sentiments on that Head I laid before you in a for- 
mer Paper: For if the filk Lines are wetted, they 
diffufc all the Electricity ; and the fame Effects hap- 
pen, when the Air is wet, be your Glafs of what 
Colour it will. 
It rnay not be improper here to obfetve, that Zaf- 
fer, which is ufed by the Glafs-makers and Ena- 
mellers, is made of Cobalt or Mundick calcined after 
the fubliming the Flowers. This being reduced to 
a very fine Powder, and mixt with twice or thrice its 
own Weight of finely powder’d Flints, is moiftened 
with Water, and put up in Barrels, in which it foon 
runs into an hard Mafs, and is called Zaffer. 
A dry Sponge hanging by a Packthread at the Fnd 
of an electrified Sword, or from the Hand of an 
Sff electrified 
