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Show -‘M_ _, '3 9044 0f Seeing. Book III. m- Book III. 0f Seeing. 90; being trajeéted through the tranfparent Compage of the Glafs, may be clear. Glafics do much (untriLUZC to the more plain pJ'Lt‘leKflOf an 011x61- ly and difiincily difcovercd. _ Glaifes being the Segments of a greater Sphaere, do require the Paper to be more diIiant from the hole, then thofe of a finaller Circle. ultereupon it happens, that the Rays paiiing through a hole, much leis then The Paper mult be fo placed about the hole, that the Ray tranfmitted feétcd with the Ray carrying the Object, and its right Ray is dilcemed in the left part of the Paper, by reafon the Rays are not interfeércd in the hole. . \ through the Center of the Glals, may be tendred perpendicular, in reference as well to the Paper, as Glafs, Ifa Concave Glafs be ufed without a Convex, it little or nothing con. tributeth to the difcerning the vifible Species painted in the Paper; bur if [he Concave be placed within the Convex-Glafs, at fuch a diPtance as is rtquifire in an optick Tube, it will much advance the clear difcovery of the Colours and Figure of the Object, to which it willadd a greater Magnitude. The Images of things are bell: feen in a Paper ( feared near a hole in an obfcure place) which difappear in a light room. Th: Firfl Hypoth- hs. The Stand II‘HNIIlCIIS The firll Hypothefis arifing out of this Opinion, is, That every Ray {treaming out of a vifible point, is propagated in a direct line 5 {0 that the Object is everted, if the Rays do not fufl'er an Interfeétion, either before or behind the hole, which would not happen, if the Rays were not carried in right Lines, but refra€ted5 whereupon , the Rays being interfecpted, the everIion of the Object will vaniIh. Another Hypothefis may be this, Thattcvery point of a vifible Objeéi is emitted into the whole Hemilphasre, with numerous Rays (Which may be proved by this @IJztinomenmr) elfc the Object will not pafs through many holes into divers, or the fame parts of the Paper. The Third Hypothens. The Third may be thus deduced, That every Ray falling upon an Opace Body, not receptive of it, as having too narrow Pores 5 whereupon the Ray is reverberatL-d into every adjoyning part of the tranfparent Medium; f0 that the Rays, reflected from one point of Incidence, do fill up the Hemifphate, which may be proved by this Experiment; Whether we feethc Object reflected, or its Image terminated into the Paper, we mull: confcfs that Rays do Iiream from every point of the Image into the Hemifpharc, by reafon the Objeft may be difcerned in every part of the adjacent Sphere, by Rays emitted from the fame point, into the whole circumference of the ‘I'nt CRUfC cf llICIlill'nlCr' Iy polition of viliblc Ohno. Comm. And the Everfion or difordcrly Polition of the vifible Images ofthings (rendring them Above Below, and the Right on the Left, and the Left on the Right Hand) doth happen, becaufe the hole beingr fmall doth exclude the tranlinil'lion of the reft of the Rays. J When every vifible point doth fill the Hemifphaere with its dilfulivc Rays it is manifel't, that more are not capable to be tranfmitted, then the little compafs of the hole can admit 3 f0 that the Object being much larger film the hole, it neccliaiily follows, either the Rays muI't be interfeéted, 01‘ elft the Obyeét make its progrefs in right Lines, or the Object muPt come "P" on the Paper in an everted Pofition ; And by how much the farther the P8" pet is removed from the hole, the Object groweth more enlarged : and 'be greater hole doth reprefent the Object in larger Dimenfions, ifit be 110‘ too exceflively large, and then the Object is not all, or very confufedly percei- ved, "'7 mfon too many Rays nor interfeéting each other, are rtanfmitwd through the hole, are becaufe too much Light obfcuteth the Objefi. And the teafon why the ViIible Semblances of things (being tranfmifled through a hole, not over-much dilated) or everted, is, that the RW" I‘treamtng from CVCT)' vifible point, run in tight, and not in crooked ":55, w ere [he Objeé‘t, cannot be tranfmitted by right lines, interfec‘ring each other, fo that the Iituation ofthc Object appears everted in the Paper, \Vllich i5 af‘. And the reafon why a little thin Plate being placed between the Objcét andthe hole in form: neat part Oppolite to it, doth obfcure the whole Image in reference to the Paper, and tendrcth‘ it in a trembling pollure, as much contracting it, which is caufed, by reafon the whole iL-inblance of the Object is inrerfeéled in every point of the hole, in which a common Vertex of two Pyramids or Cones is placed, of which one is dircft ( whofc Bafe or Termination is the radiant Surface of the Object) and the other Everted, in whofe Bafe the Image is feared in the Image of the Paper: And when the Vertex of thefe Pyramids are intercepted by fome opace Body, the courfe The Image is rrliitiirerl hya thin Hire. of the everted Rays is put off, and the Image of the Ohieft is not painted on the Paper 3 and if any part ofrhe radiation, relating to the wholeeverr- ed Pyramid, be eclipfed, thelivelinefs ofthe vifible Semblance is darkened in the Paper. . If the little Plate be put within the hole, bctWeen the Paper and ConvexGlafs, the image of the Object will be transtrrcd to the oppoiite fide, by reafon the evcrted Pyramid, which runneth to one part of the Plate, and magnifieth the Image, is cut off, and that part, which hath its Ray tranfmit~ ted to the other fide, is confpicuous. Wherefore in a Plate interpofed, the Piétureoftlie Object groweth more obfcure in fome, and more difiiné‘t in another; by reafon the Plate doth leffcn the hole, which by how much the more it is narrowed, it hath the fewerpoints of Interfeétions, and the fewer evcrted Pyramids, lhining into one Bafe ofthe Paper, whence arifeth the obfcnring of the Image relating to the Obieét ; fo that the eclipfed Pyramids, or Cones did not altogether confine on thofe that were not obfcured, but now and then were tranIinitted farther, and fomerimes deficient. Whereupon they obtained a mixture ofdiverfe light and colour, which in foine part made a confufion in the picture of the Objcét; fo that fome part of everted Pyramids, being intercepted by the narrownefs of the hole; the other that were tranfmitted through it, had more diliinét Rays, making more {irong Appulfes upon the Paper, and clear; l)' imprint the Figure and Colour of fame part of the Object upon it. The great holes through which the Object paIIeth, render the Images in fotne fort more clear, and in others more confufed. The lefs holes do make it partly more obfcure, and partly more drama, by reafon eVery point of the viIible Object doth dilfufe it felf (according to the capacity o'fthe hole ) upon the Surface of the Paper; fo that if the hole be large, it filleth a great lPaCe of the Paper, becaufe every vifible point doth emit Rays hemilphaerial1)' i Whereby it darteth its radiated Pyramids (through an open hole) whofe Vertex maketh the point sand the Hole the Bafe: or after the hole it is paintCd-in the oppofite Paper, or fome other Plane, which is alfo made by any adlacent point, whence it ari‘feth, that the fame part of the Paper doth receive the different Figures and Colours ofdivers points, which rendrcth the light more intcnfe, and the colour and Pié‘ture of the Objeét more confufed 1' But When the hole is f0 narrow that it is receptive of few points, then the irradiation ofdivcrs points of the Objcft, cannot be imprinted upon the fame Part Of the Paper 3 neither can one point be divided confufedly into many 1 Y [5 arm; A large hole rcnrlrcththc Image confle fed. |
