[ 210 ] 
round about it, from whence, by their repulfivc Pro- 
perty, they endeavour to expand themfdves on al 
Sides equally s but being ftrongly attrafledby he 
Iron a °reat Part of them are drawn oft along the 
Rod! about whofe Surface they Ukewifc form an 
Atmofpherc, which will be denfer or rarer, in pio- 
portion as the At.taflion of the Rod ts greater or 
Id's i and as the repulftve Tower of thefe Effl 
will always incrcafc in proportion with theu Den- 
litv it will follow, that whenever the Sphere is o 
ftrongly excited, that the Effluvia founding .u 
denfer than thofe furrounding the , Rod > ^ c > . ^ 
by their repulftve Property drive the Effluvia .off 
from the End of it in a Stream and that with a 
very great Velocity ; as is evident, from their ftnU 
nV a-ainft the Hand like a Blaft of Wind when 
broaghs near the End of the Rod : And as this Ve- 
locity is partly owing to the Attraftion ■ of the Rod 
to this Attraftion continuing quite o the End c , 
the Velocity of the Particles will there be greatett , 
and as they approach towards the Point, they wi 
he brou 'ht nearer together, and there ore become 
.ton in m Othc, « jf'S ; 2 
therefore if the Light is owing to die Denfity aid 
Velocity of the Effluvia, it will be viable at 
P °And £ d^uSVthus pro^cd,^! app«vn 
that whatever or diminifh 
