C 3 1 ] 
II. 
Extract of another Letter from Dr. Miles. 
Tooting, Jan. 22. 1 745 - 6 . 
I AM dubious whether I did not exprefs myfelf in a 
Manner liable to be mifunderftood, when I faid 
to this Purpofe, That I would not be mderflood to 
ejlablifh Laws by the fore-mentioned Experiments , 
but only to relate Falls 5 and that future Experi- 
ments might not confirm thefe. I did not intend 
this ffiould extend to that Experiment, which proves 
the different Nature of vitreous and refinous Effluvia 5 
which, I prefume, may be confider’d as invariable 
inherent Properties ; fo that Bodies, put into a State 
of Repulfion by the one, will be attra&ed by the 
other, &c. But the other Phenomena , as depending 
on changeable Circumftances, the Temperature of 
the Air, the Degree in which the eleftric Bodies may 
chance to be excited, the Quantity of Effluvia, and 
perhaps others to us unknown; the other Pheno- 
mena (I fay), depending on fuchlike Circumftances, 
may be variable. 
I beg Leave to inform you, that I have been making 
Trial with a Stick of Sulphur of the common Sort, 
which I made of a convenient Size, by cafting it 
into a Coffin of Paper, the Infide being of writing 
Paper : This, being excited, attra&ed the Bunch of 
Threads with great Power, and kindled common 
Spirits as quick as ever I knew it done. This was 
after Night, and I faw not what the Daylight after- 
wards difeover’d, that the infide Round of Paper ad- 
her’d 
