Referee's report by Charles Herbert Lees, on a paper 'On the velocity of sound in gases at high temperatures, and the ratio of the specific heats' by Harold Baily Dixon, Colin Campbell and A Parker Sectional Committee: Physics Recommended for publication in the 'Proceedings of the Royal Society of London'. Suggests the description of alternative methods be reduced, suggests referring to textbook by Winkelmann [?]. Refers to work by Bertholdt [?], Jongurt [?] and Cussard [?]. Addended note asks for the part of the report dealing with the measured speed of sound be deleted due to a misunderstanding on the part of the referee. [Published in the 'Proceedings of the Royal Society of London' A, 1921] Endorsed on verso as received 8 June 1921. 16 June 1921