Observed that the parabolic mirror a is at best but a very imperfect instrument, for even if the radiant were strictly a mathematical point, the cone

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Observed that the parabolic mirror a is at best but a very imperfect instrument, for even if the radiant were strictly a mathematical point, the cone of rays (shown undotted) escaping past the lips of the mirror must be lost, vintage line drawing or engraving illustration.

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Size: 4558px × 5000px
Photo credit: © Patrick Guenette / Alamy / Afripics
License: Royalty Free
Model Released: No

Keywords: art, black, drawing, engraved, engraving, hutchinson, illustration, light, lighthouse, line, mirror, miscellaneous, optics, parabolic, paraboloid, reflection, reflector, vector, vectors, vintage, white