Opticks Book by Isaac Newton(37)

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firſt Prifms be either white and circular, or co-

loured and rectangular once it falls on the third. Exper. 6. within the middle of 2 skinny Boards I created spherical holes a 3rd a part of an in. in diameter, and within the Window - ſhut a way broader hole being created to let into my dark- ned Chamber an oversized Beam of the Sun's Light; I placed a Priſm behind the border that beam to refract it towards the oppoſite Wall, and cloſe behind the Priſm I fastened one in every of the Boards, in ſuch manner that the center of the refracted lightweight would possibly would possibly through the opening created in it, and therefore the and therefore the intercepted by the Board. Then at the diſtance of concerning twelve Feet from the within the I fastened different|the opposite} Board in ſuch man- ner that the center of the refracted lightweight that came through the opening within the firſt Board and got hold of got hold of Wall would possibly would possibly through the opening during this other Board, and therefore the and therefore the intercepted by the Board would possibly paint upon it the colored Spectrum of the Sun And cloſe behind this Board I fastened another Priſm to re- fract the sunshine that came through the opening. Then I came came to the firſt Priſm, and by turning it ſlowly to and fro concerning its Axis, I cauſed the Image that got hold of got hold of Board to maneuver up and down upon that Board, that all its elements would possibly would possibly would possibly through the opening therein Board and come across come across behind it. And within the unit of time, I noted the places on the oppoſite Wall to that that lightweight once its Refraction within the within the within the and by the distinction of the places I found that the sunshine that being moſt refracted within the

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