LETTERS unsightly layers of ammonium salts after storage of a Less Ammonium Chloride few days or weeks. This nuisance can be largely To the Editor: Two interesting accounts [DAVIS AND NECKERS, eliminated by proper storage of these concentrated rea"An ammonium chloride chimney," J. CHEM.EDUC., gents. Most stock rooms have shelves, one above the 18, 292 (1941), and "Out of the editor's basket," ibid., other. The concentrated acids and bases may be stored 18, 347 (1'941)l have recently appeared in this journal on separate shelves, the one of least density on the regarding ammonium chloride growths. Most chem- highest shelf, and the one of greatest density on the ists, however, are continually annoyed by the accumu- bottom shelf. Such an arrangement will reduce the lation of ammonium chloride deposits on bottles and accumulation of these unsightly deposits to a minimum. equipment around chemical laboratories and stock RALPH E. DUNBAR rooms. Bottles of concentrated acids and of amNORTHDAKOTA AGRICULTURAL COLLEGE FARGO, Nonnr DAKOTA monium hydroxide are usually coated with heavy and
