Opticks 1717 - Up

Merk- one 2nd the fatix *part of I the’Light ill
one and the fame pIaceS according to ‘the va- ,
rious Inclinations of the Paper, appeared irz me
cafe white, iri another yellow or red; in a third.
blue, wl$ft: the Confine of Light alld Shadow,
and the RefraAions of the,Priif? in all tki’e ca-
fe; remained the fame.
Eipr. 3. §uch another Experiment may be
morg eafily tried as foIlows. Let ti broad beam
of the ‘Sun’s Light coming into a dark Cham-
&T. through a hole in the ‘Window-i$ut be rev
fia&ed II a large Prifm A 13 C , [ 111 F&q 3. ‘J
$,rhofe re P ratiing Angle C is IIIOE than 60 Der
grces, and fo foon as it colncs a’ut Of the Prifiq
lei it fall tiFon the white Paper .DE glewed upon
‘2, MT Piane ; and this Light, when the Pa
per is perpendicular. to i,t, as ‘tis reprcfclltcd in ,
DE,’ will appear perfe&ly white ‘upon the Pa
per, hut when the Paper is very much inclin’d
ta it in fu,& a manner as to keep al~vays pn~:al~
llel to the 4x1s of ,yhe IWin, the whitcMs~,of
the whole Light upon the Paper will accord~r~g
to the inclination of the Paper this ulnas or/that
way? c’lr+ge either iato yellbW and red, bs in
the po&~re He, or into ,blue arzd viokt,~ ‘as in
the ‘po@~e $6, And if the L$h~ bcfkc i&fall
upon the Paper be twjce ~&+&erl the fame
Way by two; parallel Prii-ms, thcfe Colaurs will
‘becbme the more canl’picuous. Hex all the
middle ptir~s qf the brqad bcatn ‘of white Light
vhicl! fell upon the Paper, did WirhcM any
@onfine la%3ha&sw to modif it: p ~~xco~ne ‘con
Sour’d all :OW v&& &le Lini F arm (M&u2 the
@?J~.u ]ahg always the ‘fame $1 111~ @ddle$
,,