9. The Objeft appearing doublejboth images appear with a 
fainter colour 5 and (bmetiiBes one part of the fame Jpeaes h 
obfcurer than the other* 
10. To an attentive Eyej one ofthefe Images will appear 
higher than the other. 
1 1 Jn a certain pofition the Im^ge of an Ob;e£i:/een through 
this Body^ appears but fingle^ like as through any other 
Tranfparent Body. 
1 2* We have alio found a pofition^ wherein the Ob)eft ap* 
pearsfixfold> 
13.. If any of the obtufe Angles of this Prifmebe divide<i 
into^woeqqal parts by aline, a^d the vifual raysdo pais from: 
the Eye to the Objeft through that linej or its parallel^ both 
Images will meet in that line, or in another parallel to it. 
14. Whereas ObjeiSs^ fcen through Diaphanous Bodie.s 
are wont to remain conftantly in the fame place, in what man- 
ner foeyer the tranfparent Body be movedj nor the Image on 
the Surface niove except the Objed be moved 3 we have ob« 
fervedhcrej that one of the Images is moveable^ the other 
remaining fix 5 although there be a way alfo, to make the 
fixed image moveabk^and the moveable fix in the iame Chry-^ 
ftal^ and another, to make both moveable. 
15^. The Moveable Image doth not move at random^ but 
^[yjdcsfs about th^ Fixed, which while it turret h aboutj it never 
defciibeth a perfeft Circle but in one cafe. 
i 16. Biopricks ttzchy that a Diaphanoas* Body, having one 
' only furfacej fends from one Obj^d but one Image refraftecf 
to the Eye 5 and having more Surfaces than one, it reprefeots 
one Image in each ^ But whereas in our fubftaoee there occurs 
but one plain fuperficies to the Eye and yet a dou- 
ble image of one Objeft ^ it concerned us to confider, whence 
this double image might be caufed. T23!S£>.ways offer'd them* 
felvesto m^U£fle£iion and Refra3ioff^ow Refle&io^ eould per- 
ibrm it,was difficult to find.EoFjhaving dulled the clearnefs o£ 
the two plain fides of our Chryftallin Prifmcj thereby ta 
gjiak^ them unfit for Elefleding the light 3 the Rays being di- 
re&cd . through its wppes andiQwermo][ifuperfides3the image 
