Referee's report by Robert Robertson, on a paper 'Photographic investigation of flame movements in gaseous explosions. Parts IV, V and VI' by William Arthur Bone and Reginald P Fraser Sectional committee: Chemistry [Report focuses on parts IV and V of the paper]. Recommended for publication in Philosophical Transactions, in full. It is an interesting and important contribution. [Published in Philosophical Transactions A, 1932]. Endorsed on verso as received 4 July 1931. 1 July 1931