Serial Suggestion. Submitted by Remarks of I.S.S.B. No. 2 contd. 3. 4. 5. -2movement, energy and full equipment would be made on the men's minds just before their departure. Unconscious sources of propaganda concerning morale can be created by the equally simple expedient of instructing infantry units in the neighbourhood to route-march past the camps; the men should be induced to sing at that point in the march. A limited number of unconscious sources of officer rank therefore the more important can be created by causing "mock-ups" of, say, extra heavy A.A.