Light visible and invisible : a series of lectures delivered at the Royal Institution of Great Britain, at Christmas, 1896 (1897)
Thompson, Silvanus Phillips, 1851-1916, Royal Institution of Great Britain · New York : Macmillan · leaf 147
double-imageprism is rotated it is observed that when, as in Fig.88, the two images are in the position vertically aboveone another, the ordinary is cut off, while the extra-ordinary is transmitted. On turning round the double-image prism the ordinary image gradually appears, whilethe extraordinary… … Fig. 90. are equally bright, the directions of the resolved vibra-tions being as shown by the fine lines in Fig. 90. Now, having proved that the spar does split thelight into two beams in which the vibrations aremoving in different ways, we have yet to consider howit effects this. The resolution of…
Light · X-rays
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