Letter from John David Griffith Davies, to Aeronautical Research Committee, regarding a paper 'The air wave surrounding an expanding sphere' by Geoffrey Ingram Taylor Sectional Committee: Physics The author thinks the Aeronautical Research Committee ought to have copies of the paper. Equires if they could provide an order as soon as possible. [Published in the 'Proceedings of the Royal Society of London'] No received date. 29 February 1940