[ 72 ] 
tindtj the red commonly prevailing, and fuffufing 
all the other colours, as in N° 1. upon the ffeel ; 
though I attribute the confufion of the colours in 
that circle, in part, to the needle having been feveral 
times accidentally broken from the cement which 
l'upported it, and to its not having been replaced ex- 
actly as before. 
6. The laft formed colours are always the mod; 
vivid, as appears very diftindtly in the reds of N° i 
upon the Heel. Alfo the laft formed rings lie clofer 
to one another than the firflr. 
y. Thefe rings may be brufhed with a feather, and 
even wetted, or a finger may be drawn over them, 
without their receiving any injury ; but they eafiiy 
peel off, when fcratched with one’s nail, or any thing 
that is fharp, the innermoff rings being the mod dif- 
ficult to erafe. 
8. The firff circles are fometimes covered with a 
quantity of black duff; part of which however may 
be wiped off with a feather, fo as to fhow the co- 
lours under it. An attempt to wipe off more, on 
the rough fide of the fteel, took off the colours along 
with it ; but more than half yet remains, with the 
duff upon it, as it was firff formed. 
9. It makes no difference whether the eledtric mat- 
ter iffue from the pointed body upon the plate, or 
from the plate upon the pointed body ; tire plate op- 
pofed to the point being marked exactly alike in both 
cafes. Alfo the points themfelves, from which the 
fire iffues, or at which it enters, are coloured to a con- 
fiderable diffance, often about half an inch, but not 
very diftindtly. The colours likewife return here, in 
concentric rings, as upon the plate. 
i o. I think 
