Up to the present time, in experiments on diffraction there ...

Up to the present time, in experiments on diffraction there has been no instrument, except a magnifying-glass, which could be used with profit; and this may perhaps be one of the reasons why in this field of physical optics we are so backward, and why we know so little of the laws of this modification of light.

Joseph von Fraunhofer

Prismatic and Diffraction Spectra: Memoirs (1899) Tr. & Ed. J. S. Ames p. 13

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Joseph von Fraunhofer Quotes

$Up to the present time, in experiments on diffraction there has been no instrument, except a magnifying-glass, which could be used with profit; and...$

$Up to the present time, in experiments on diffraction there has been no instrument, except a magnifying-glass, which could be used with profit; and...$

$Up to the present time, in experiments on diffraction there has been no instrument, except a magnifying-glass, which could be used with profit; and...$

$Up to the present time, in experiments on diffraction there has been no instrument, except a magnifying-glass, which could be used with profit; and...$