SALV. See here is the glaſſe, which I would have to be placed
cloſe to the other. But firſt let us go yonder towards the reflection
of that flat one, and attentively obſerve its clarity; ſee how
bright it is here where it ſhines, and how diſtinctly one may diſcern
theſe ſmall unevenneſſes in the Wall.
cloſe to the other. But firſt let us go yonder towards the reflection
of that flat one, and attentively obſerve its clarity; ſee how
bright it is here where it ſhines, and how diſtinctly one may diſcern
theſe ſmall unevenneſſes in the Wall.
SIMPL. I have ſeen and very well obſerved the ſame, now place
the other glaſſe by the ſide of the firſt.
the other glaſſe by the ſide of the firſt.
SALV. See where it is. It was placed there aſſoon as you
gan to look upon the Walls ſmall unevenneſſes, and you
ved it not, ſo great was the encreaſe of the light all over the reſt of
the Wall. Now take away the flat glaſſe. Behold now all
ction removed, though the great convex glaſſe ſtill remaineth.
Remove this alſo, and place it there again if you pleaſe, and you
ſhall ſee no alteration of light in all the Wall. See here then
monſtrated to ſenſe, that the reflection of the Sun, made upon a
ſpherical convex glaſſe, doth not ſenſibly illuminate the places neer
unto it. Now what ſay you to this experiment?
gan to look upon the Walls ſmall unevenneſſes, and you
ved it not, ſo great was the encreaſe of the light all over the reſt of
the Wall. Now take away the flat glaſſe. Behold now all
ction removed, though the great convex glaſſe ſtill remaineth.
Remove this alſo, and place it there again if you pleaſe, and you
ſhall ſee no alteration of light in all the Wall. See here then
monſtrated to ſenſe, that the reflection of the Sun, made upon a
ſpherical convex glaſſe, doth not ſenſibly illuminate the places neer
unto it. Now what ſay you to this experiment?
SIMPL. I am afraid that there may be ſome Leigerdemain,
uſed in this affair; yet in beholding that glaſſe I ſee it dart forth
a great ſplendor, which dazleth my eyes; and that which
ports moſt of all, I ſee it from what place ſoever I look upon it;
and I ſee it go changing ſituation upon the ſuperficies of the glaſſe,
which way ſoever I place my ſelf to look upon it; a neceſſary
gument, that the light is livelily reflected towards every ſide, and
conſequently, as ſtrongly upon all that Wall, as upon my eye.
uſed in this affair; yet in beholding that glaſſe I ſee it dart forth
a great ſplendor, which dazleth my eyes; and that which
ports moſt of all, I ſee it from what place ſoever I look upon it;
and I ſee it go changing ſituation upon the ſuperficies of the glaſſe,
which way ſoever I place my ſelf to look upon it; a neceſſary
gument, that the light is livelily reflected towards every ſide, and
conſequently, as ſtrongly upon all that Wall, as upon my eye.
SALV. Now you ſee how cautiouſly and reſervedly you ought
to proceed in lending your aſſent to that, which diſcourſe alone
preſenteth to you. There is no doubt but that this which you ſay,
carrieth with it probability enough, yet you may ſee, how
ble experience proves the contrary.
to proceed in lending your aſſent to that, which diſcourſe alone
preſenteth to you. There is no doubt but that this which you ſay,
carrieth with it probability enough, yet you may ſee, how
ble experience proves the contrary.
SIMPL. How then doth this come to paſs?
SALV. I will deliver you my thoughts thereof, but I cannot
tell how you may be pleaſ'd therewith. And firſt, that lively
ſplendor which you ſee upon the glaſs, and which you think
pieth a good part thereof, is nothing near ſo great, nay is very
ceeding ſmall; but its livelineſs occaſioneth in your eye, (by means
of the reflection made on the humidity of the extream parts of the
eye-brows, which diſtendeth upon the pupil) an adventitious
ation, like to that blaze which we think we ſee about the flame of
a candle placed at ſome diſtance; or if you will, you may
reſemble it to the adventitious ſplendor of a ſtar; for if you ſhould
compare the ſmall body v. g. of the Canicula, ſeen in the day time
with the Teleſcope, when it is ſeen without ſuch irradiation, with
the ſame ſeen by night by the eye it ſelf, you will doubtleſs
prehend that being irradiated, it appeareth above a thouſand
tell how you may be pleaſ'd therewith. And firſt, that lively
ſplendor which you ſee upon the glaſs, and which you think
pieth a good part thereof, is nothing near ſo great, nay is very
ceeding ſmall; but its livelineſs occaſioneth in your eye, (by means
of the reflection made on the humidity of the extream parts of the
eye-brows, which diſtendeth upon the pupil) an adventitious
ation, like to that blaze which we think we ſee about the flame of
a candle placed at ſome diſtance; or if you will, you may
reſemble it to the adventitious ſplendor of a ſtar; for if you ſhould
compare the ſmall body v. g. of the Canicula, ſeen in the day time
with the Teleſcope, when it is ſeen without ſuch irradiation, with
the ſame ſeen by night by the eye it ſelf, you will doubtleſs
prehend that being irradiated, it appeareth above a thouſand
zoom in
zoom out
zoom area
full page
page width
set mark
remove mark
get reference
digilib