C 4087 ) 
31 Latin Letter writcen to the Publiffier April 9. 1672. 0. ft/ 
by Ignatim Gaflon Pardies P. Prof, of the Mathema- 
ticks in the Parifian Colledgc of Clermom 5 coatainiog 
fome Animadver{ionsuponMr.//tf^i:iV^n?^^;i^ Prof, of the 
Mathematicks in the Univerlicy of Cambridge^ his Tkeory of 
L^^^ printed in N". ^ 
T Eg^ ingeniojijfmam Hypothefin de Lumine Coloribus 
\_j CJariJfimi^QwtonL Et quia nonnullam Ego operam dedi 
in ifiacontemplatione atque Experimentis peragendis^ perfmbam ad 
Tepauca, qu£ mihi circa mvam ifiam doUrinam occurrerunt. 
Circaipfcim Luminis naturam illud profeUo extraordinarmm vide* 
tur^ quod ait vir eruditijjimus j Lumen eonjiare ex aggregatione 
infinitorum propemodum radiorum^ qui fudpte indole (mm qutjqm 
€Qloremreferantretineanpque^ atque adeh nati apti (int mta qm^ 
dam^ pecuhari ratione, plus alij^ alij minus ^ refringi^ :^di6^ 
ejufmodi^ dum promifcui in aperto lumim confu^dumur, nuUatenus 
di/cerni, [ed candor em potius referre i in refraUiom veto fmguUs 
mius coloris ab aliis alterius color is fecerni^ ^ hoc modo (ectetos^ 
fub proprio ^ nativo colore appar ere : Ea corpora fub aliquo colore^ 
V. rubro^^ videri^ qum apt a Jint refleHere am tranfmittere radi^ 
ej fblummodl rubros^ tic. 
Iji^c tarn ex traor dinar ia Hypothefis^ qu£, ipfe obfervat^ Dh 
optriae fundamenta evertit, praxefque haSlenus infiitutas inutiles 
reddity iota nititur illo Experimento Prifmatis Cry flallini, ubi rat 
dij per foramm feneftrce intra obfcurum cubiculum ingrefi^ ac deinde 
in parietem impaUi^ autin cbarta recepti, n$n in rotundum confor* 
mati^ ut ipli, ad regulas refra<9:ionum receptas attendentij 
expedandum vWebatur, fed in oblongamfguram exten[i apparu- 
ermt : Vnde conclujtt^ oblongam ejufinodi figuram ex eo ep^ quod 
tionnulli radij minus y nonnuUi magis refringerentur^ 
Sed mihiquidem videtur juxta commuaes t3 receptas Dioptrics 
\tgQ% figuramillamy non retnndam^ fed oblongamepoportere. Cum 
enimradij ex oppofyis difci Solaris partibus pr ocedentes ^ variam 
babeant in ipfo tranjitu Prifmatis inclinationem, varie quoque re- , 
fringi debent s ut chm unorum inclinatio 30 faltem minutis major 
ft inclinatioM aliorum , major quoque evadat illorum B^efraHio^ 
