( 5005 ) 
J. Whether rays^ which are endued with particular degrees 
of refrangibih'ty, when they are by any means fepafatedj have 
particular colours conftantty belonging to them, vin^^ the leaft 
refrangiblej^^W<?^ 5 the moft refraogiblej^^^/^ Violet the mid- 
dXc^Sea-green-^mA others^other colours } And on the contrary? 
4^ Whether the colour of any fort of rays apart may be 
changed by refradion ? 
5. Whether colours by coalefcing do really change one an~ 
other to produce a new colour,or produce it by mixing only .<? 
6* Whether a due mixture of rays, indued with all variety 
of colours, produces Light perfectly like that of the SuOjaod 
which hath all the fame properties^and exhibits the fame Phs-. 
mm ena > 
7. Whether the component colours of each mixture be re^ 
ally changed 5 or be only feparated, when from that mixture 
various colours are produced again by Refradlion > 
8* Whether there be any other colours produced by refra- 
ction than luch, as ought to refult from the colours belonging 
to the diverfly refrangible rays by their being feparated or 
mixed by that refradlion > 
To determine by Experiments thefe and fuch like j^^res 
which involve the propounded Theory, feems the molt pro* 
per and direiSl way to a conclufion* And therefore 1 could 
wifli all objeftions were fufpended, taken from l^jpothefes or 
any other heads than thefe two ^ Of fliewing the infufBciency 
of Experiments to determine thefe ^^re/ or prove any other 
parts of my Theory, by affigning the flaws and defeats in my 
conclufioiss drawn from them ; Or of producing other Ex- 
periments which direftly con tradid: mCj if any fuch may feem 
to occur. For if the ExperimerftSj which I urge, be defedlive, 
it cannot be difficult tofliow the defefts > but if valid , then by 
proving the Theory they muft render all Objedtions invalid. 
So far this accurate Tropdfer > whofe Method appearing to be 
moftgenuine and proper CO the purpofe it is propounded for, 
and deferviog therefore to be confidered and put to trial by 
Philofophers, abroad as well as at home 5 the Publi flier, to 
inviceand gratify Forraigners, was willing to deliver the a- 
boVef ecited Extract of Mr* Nemons Letter in the language 
alfoof theLearnedjasfolloweth 3 Zzzz i ' Ex- 
