الفهرس 
DEDICATED TOMY ARENTS AND REFFATOnly 14 pages are availabe for public view
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Abstract
Historical and general introduction to diffraction techniques:
If crystals were composed of regularly spaced atoms which might act as scattering centers for X-rays, and if X-rays e electromagnetic waves of wavelength about equal to interatomic distance in crystals, then it should be possible to diffract X-rays by means of crystals. This was, how things were reasoned by von Laue (7) in (1912) when he took up the problem. Before (1912) mineralogists and crystallographers had accumulated knowledge about crystals, mainly by measurement of interfacial angles, chemical analysis, and determination of physical properties.
There was, anyhow, little knowledge about the interior structure guesses had been made, namely, that crystals are built up by repeating some unit, which may be an atom or a separated by distances of the order of magnitude of one or two Angstroms. On the other hand, there were only indications that X-rays might be electromagnetic waves about the same order of magnitude in wavelength. But at that time the phenomenon of diffraction was very well understood. It was known that visible light is diffracted by a set of regularly spaced scattering objects, provided that the wavelength of the wave motion is of the same order of magnitude as the repeat distance between the scattering centers.