Letter from John David Griffith Davies, to William Edward Curtis, regarding a paper 'Supersonic dispersion in gases II. Air containing water vapour' by M Mokhtar and E G Richardson Sectional Committee: Physics The paper he Communicated has been passed for publication is due course. However, as a Government official has suggested that it contains information that might be useful to the enemy, the paper will be withheld from distribution until after the war. [Published in the 'Proceedings of the Royal Society of London'] No received date. 24 January 1940