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-------------------+-----------+-------- The distance between the Middles of the | | brightest Light of the second and third | | Fringes | 1/170 | 1/31 -------------------------------------------+-----------+-------- The breadth of the luminous Part (green, | | white, yellow, and red) of the first | | Fringe | 1/170 | 1/32 -------------------------------------------+-----------+-------- The breadth of the darker Space between | | the first and second Fringes | 1/240 | 1/45 -------------------------------------------+-----------+-------- The breadth of the luminous Part of the | | second Fringe | 1/290 | 1/55 -------------------------------------------+-----------+-------- The breadth of the darker Space between | | the second and third Fringes | 1/340 | 1/63 -------------------------------------------+-----------+-------- These Measures I took by letting the Shadow of the Hair, at half a Foot distance, fall so obliquely on the Scale, as to appear twelve times broader than when it fell perpendicularly on it at the same distance, and setting down in this Table the twelfth part of the Measures I then took. _Obs._ 4. When the Shadow and Fringes were cast obliquely upon a smooth white Body, and that Body was removed farther and farther from the Hair, the first Fringe began to appear and look brighter than the rest of the Light at the distance of less than a quarter of an Inch from the Hair, and the dark Line or Shadow between that and the second Fringe began to appear at a less distance from the Hair than that of the third part of an Inch. The second Fringe began to appear at a distance from the Hair of less than half an Inch, and the Shadow between that and the third Fringe at a distance less than an inch, and the third Fringe at a distance less than three Inches. At greater distances they became much more sensible, but kept very nearly the same proportion of their breadths and intervals which they had at their first appearing. For the distance between the middle of the first, and middle of the second Fringe, was to the distance between the middle of the second and middle of the third Fringe, as three to two, or ten to seven. And the last of these two distances was equal to the
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