“…Complicated diffraction patterns have been reported from 2,4,6-trinitrotoluene (Ito, 1950;Burkardt & Bryden, 1954), 1,3,6,8-tetranitronaphthalene (Gol'der et al, 1952 and some other crystals studied by Ito. In particular there appear to be resemblances between the patterns obtained from trinitrotoluene and th.ose studied in the present series of papers. One difference is, however, the variability of the trinitrotoluene patterns; the patterns from (I) and a-l,2:4,5-tetrachlorobenzene were always found to be the same, despite variations in experimental conditions.…”