( 42 <* ) 
times feem to meet and joftle ; and at other times to fepa- 
rate, and fly one another. But this Motion was only Opti- 
ca), and occafioned by the Eye of the Spe&ator being 
carried away with the Earth into the Eaft ; whilft the ex- 
ceeding rare Vapour of which thofe Beams did conflft, 
being, as I take it, railed far above the Atmofphere, was 
either wholly left behind, or elfe followed with but part 
of irs Velocity, and therefore could not but feem to re- 
cede and move the contrary Way. And after the fame 
manner as the Stars that go near the £enirh, pafs over 
thofe Vertical Circles which border on the Meridian, 
much fwifter than thofe Stars which are more diftant 
therefrom ; fo thefe luminous Rays would feem to recede 
fafler from Eafl to Weft, as their Bafes were nearer the 
Eye of the Spectator ; and e contra, flower as they were 
further off 
Nor are we to think it ftrange, if after fo great a 
Quantity of luminous Vapour had been carried up into 
the Ether out of the Pores of the Earth, the Caufe of its 
EfFervefcence at length abating, or perhaps the Matter 
thereof confumed ; thefe Effluvia fhould at length fubfide, 
and form thofe two bright Lamina which we have defc 
cribed, and whofe Edges being turn’d to us were capa- 
ble to emit fo much Light that we might read by them. 
I chcofe to call them Lamina, becaufe, without doubt, 
though they were but thin, they fpread Horizontally 
over a large Tratft of the Earth Surface. And whilft this 
luminous Matter dropt down from the upper Plate to the 
under, the many Ifttle white Columns were formed be- 
tween them by its Defcent, only vifible for the Moment 
of their Fall. Thefe by the Swiftnefs with which they 
vanifhed and their great Number, {hewing themfelves and 
difappearing without any order, exhibited a very odd 
Appeareuce; thole on the Right feeming fometimes to 
drive and pufh thofe on the left, and vies verfa> 
I 
