turn CfHcis^ can have to do with a cloudy day > For, if the Exf e- 
rimentum Cm« (which is that which I depend on) can have no- 
thing to do with a cloudy day, then is it tonopurpofe to talk of a 
cloudy day in thefirft Experinienc,whichdoes but lead on to that. 
But if this fatisfie not, let the tranfaHkns N. 83./. 4060, be con- 
fulted : For. there I tell you, how ly applying a Le;$s to the Prifm, 
the ftreight edges of the oblong Image became diftinfter than they 
would have been withounhe Lem : A circumftance which cannot 
happen in lAv.Lwuis cafe of a bright Cloud. 
¥oY the Fofitm of the Frifm-^ I tell you A^So. /.3076, that it 
was placed at the Sun's entrance into the Chamber,and in/> 3085.! 
bad to make a hole in the fl3Ut,and there place the Prifm^and in the 
next page I fay again, that the Prifm ABC is to be fet chfe by the 
hole F of the window EG ; and accordingly reprefent it clofe in 
the Figure. hKoiu pag. 3077 I tell you, chat the diftanceof the 
Image from the bole or fr//5» was 22 foot ; which is as much as to 
fay, that the Prifm (fuppofe that fide of it next the hole) was as 
farfrom the Image as the hole it felf was, and confequently that 
the Prifm and Hole were contiguous* Alfo in /♦3078, where inftead 
of the Window fliuc I made ufe of a hole in a loofe board , I tell 
you explrefly, that I placed the board clofe behind the Prifm. All 
thefepaflages are in my very firft Letter about Colours ; and who 
therefore would imagine, that any one that had read that Letter 
fliouldfomuch asfui>ea,that Iplaced thePrifin, I fay notatfo 
greatadiftanceasMr.L/;?^ fuppofes^buc at any diftance worth 
confidering ? 
Laftly, for the Pojition of the Image , it is reprefented tranfvers 
to the axis of the Prifm in thefiguresiVr.8o./>.3o86. i\Z'.83./^.4o6 r, 
and iV.85. /^.5016. Andin i\/.88./>.5093, wherelmadeufeof two 
crofs Prifins, I tell you exprefly , that the Image was crofs to both 
of them at an angle of 45 degrees. The calcu ations alfo N. 80. f. 
3077. are not to be underftood without fuppofing the Image crofs. 
Nor are my notions about different Refrangibility otherwife in- 
telligible: ForinMr.L/;?/i^/sfuppofition, the rays that go to the 
two ends of the Image,are cqually^refrafted.So for colours,the red^ 
according to my defcription, falls at one end of the Image, and the 
hUw at the other ; which cannot happen but in a tranfvers Image, 
The fame pofitioT) is alfodemonftrable from what I faid in iVT* 80. 
3076, about turning the long Image into a round one, by the 
Dddd contrary 
