在翻译the coming of materials science时，有一段我是这么翻译的：

1912年，Max von Laue (1879-1960)在慕尼黑吩咐两位助手Paul Knipping和Walter Friedrich 将一束(多色)X射线通过硫酸铜晶体然后打在一块感光板上。做完这个他们立刻用闪锌矿做了同样的实验：他们观察到了晶体的第一组衍射斑点。Laue是在与Paul Ewald的交流中受到启发而进行这个实验的。Paul Ewald向他指出，晶体中的原子不仅是只能周期性排列，其间距还要远小于光的波长。(这是从Avogadro常数和对晶体密度的测量很简单就得出的结果。)

 这和金属所的翻译不一样。当时我只是根据英文认为应该这么翻译，但对相关史实并不清楚。前两天看那本Fifty Years of X-ray Diffraction（http://blog.sciencenet.cn/blog-664617-1150078.html），第四章中有一段解决了这个问题。Laue确实是受Paul Ewald的启发做的他那个著名实验。

Laue suggested that they meet the next day-it was probably late in January 1912-in the Institute and discuss before and after supper at his home. They met as arranged and took a detour through the Englische Garten, a park whose entrance was not far from the University.
After having crossed the traffic on the Ludwigsstrasse, Ewald began telling Laue of the general problem he had been working on, because, to his astonishment, Laue had no knowledge of the problem. He explained how, in contrast to the usual theory of dispersion he assumed the resonators to be situated in a lattice array. Laue asked for the reason of this assumption. Ewald answered that crystals were thought to have such internal regularity. This seemed new to Laue. Meanwhile they were entering the park, when Laue asked: ‘what is the distance between the resonators?’ To this Ewald answered that it was very small compared to the wave-length of visible light, perhaps l/500 or l/1000 of the wave-length, but that an exact value could not be given because of the unknown nature of the ‘molecules inttgrantes’ or ‘particles’ of the structure theory; that, however, the exact distance was immaterial for his problem because it was sufficient to know that it was only a minute fraction of the wave-length。