Brain sectioning has been improved through gelatin embedding so that more than forty precisely oriented serial sections can be obtained from a single brain. Since the embedding gelatin requires no fixation, it can be removed from the sections prior to staining by simple warming. The reduction of Berlin blue dye commonly observed after staining by the Mulligan method has been found to be at least partly due to light in the UV to near UV range. Dye reduction is significantly inhibited by postfixation in 25% acetic acid.