Opticks 1717 - Up

I- ?a I
fha’t hole to th@ P&l. For i‘o the Circles AG,
B 13 i~llC$ the Seti, ~~rOUld 1lOt aIly lOll$Jer Zlflf\\‘er
to the whok Difque of the sun, but only to
that part of it which could be fee11 from the
~rifm through that hole, that is to the :qyarent
magnitude of that hole viewed from the
Prifh, 4jut that thefe Circles may anfker more
diitin&ly to thar hol.e, a Lens is to be placed by
the Priiin to cait: the Image of the hole, (that
is, every and of the Circles A G, BH, &.) difiin&ly
upon the Paper at I? T, after Such a
mai~ner as by a Lens placed at a Window the
Species of Objckts abroad are cait diilin&ly.up;
on .a Paper within the Room, and the reC‘tilinear
Sides of the oblong folar Image in the fifth
Experiment became dif1inCt without ally Penumbra,
If this,be done it will not be neceiG~ry
to place that hole very far OB; 110 not beyone
the Window. And therefore initead of that
hole, I ufed the hole in the Window-fhut as
follows.
Exper. II. In the Sun’s Light let into my
darkned Chamber through ;I ir~xA round hole
in my \\‘indon~-ikut , ilt >IbOUt tel1 01’ tWClVe
Fixt from the Window, % placed a Ecns , by
which the Image of the hole m@ht be dil’Ein&-
ly caf? upon a Sheet of white Paper, placed qt
the difkwx of fix, eight, ten or twelve Feet
from the Lens. For according to the differexxe
of the Lenlks I ufed various dii.tancesg,
which I think not worth the \vhilc to dei‘cribcA
The11 immediately after thk LOIIS I phced a
Frih, by which the trajekd I..,iglJt: might bc
refraCted either upwwds or fidelways, and therebY