RADIORVM DIVERSICOLORVM. 187 



medio in aliiid quodciinque traQfcuntium afllgnari 

 potcft. 



Scholion i. 



39. Hinc iam discrimcn intcr hanc hypotlic- 

 fin ct priorcm , qua olim yfus cram, hiculcntcr 

 pcrfpicitur. Fingamus cnim quotcunque mcdia dia- 

 phana A, B, C, D etc. quorum primum A fit acr, 

 rehqua vero contuiuo ita fiant denfiora, vt rcfradlio 

 inedia cx quolibct in (cqucns fit cadcm 3rw:i, 

 idcoquc refmcftio media fit cx A in C — ///' : i , cx 

 A in D=:m' : i etc. Hinc autcm ex quohbet mc- 

 dio in fequens tranfcundo rcfracftioncs extremae noa 

 prodibunt cacdcm , vti in priori hypothcfi , fed ita 

 fe habcbunt : 



In tranfitu 



cx A in B 

 ex B in C 

 ex C in D 



refracflio 

 media 



refra^ftio 

 rubra 



m 

 m 

 m 



rcfraclio 

 violacea 



y 



iV 



I 

 I 



Etfi crgo rcfraclio mcdia vtiquc eft eadcm , rcfra» 

 diones extrcmac tamcn discrcpant , ct contmuo pro- 

 pius ad raediam conucrgunt , ita vt quo dcnfiora 

 fli rint ambo mcdia , co minus discrimen iutcr refra- 

 (itiones extrcmas intcrccdat. 



Aa 2 



Scho- 



