panying them J if they perform no more, than fliorter ones. 
Where^ by the by, he cakes notice, that he knows not yet, what 
Jlperture Signox Campani giytsio his Glaffes, feeing he hath as 
yet fignified nothing of it ; but that the (mail one, fent by him 
to Cardinal Antonio, hath no more Aperture^ than ordinary ones 
ought to have. 
He promifes withall , that he will explicate this way in his 
Treati[B of the ufefulmfs ofTeleJoopes^ where he intends to affign 
the Bignefs of che Diameter of all the 'Planets, and their propor- 
tion to that of th@ Sun ; as alfo^ that of the Stars ^ which he e- 
fteerrjs yet much lefs, than all thofe have done, that have wit- 
ten of it hitherto ; not believing, that the Great Dog, which ap- 
pears to be the faireft Star of the Firmament, iiath 2 Seconds in 
Diameter^ nor that thofe, which are counted of the fixth Mag- 
nitude, have 20 thirds 5 nor thinking, that all the Stars, that are 
in the Firmament, do enlighten the Earth as much as a Luminous 
Body of io[econds in Diameter would do, orjbecaufe there is 
but one half of them at the fame time above our Hori^on^ as a 
Body of i^fesondsin Diameter and as the 18432^^ part of the 
tSaw would enlighten us, or as the 6*2^?^ would doj if we were 14 
times more diftant from itj than Saturn, and 137 times further, 
than the Earth: Which, he faith^ would not be credible, if he 
did not endeavor to evince it both by Experience and l^afon. 
And he doubts not, but that Venus^ although flie fends us no 
Light but what is refle<iled, does fometimes enlighten the Earth 
more, than all the Stars together. Yet he would not have us i- 
magine,from what he hath fpoken of the fmalnefs of the Stars, 
that Telefcepes do not magnifie them by reafon of their great di- 
ftance, as they do Planets ; for this he judgcth a Vulgar Error, 
to be renounced. Telefcspes magnifie ih^ Stars faith he^ as 
much in proportion, as they do all other Bodies, feeing that the 
demonftration of their magnifying is made even upon Parallel 
rays, which do fuppofe an infinite diftance , though the Stars 
have none ftich : And if the Telefcopes did not magnifie the Stars, 
how could they make us fee fome of the fiftieth, and it may 
be fome of the hundretb, and twohundreth Magnitude 5 as they 
do^ and as they would ftiew yet much lefTer ones , if they did 
magnifie more > 
I % Mr. 
