Second referee's report by Edward Arthur Milne, on a paper 'Time-lag in a control system' by A Callender, Douglas Rayner Hartree and A Porter Sectional committee: Mathematics The authors have added a new addenda, but this shouldn't be published. It has taken him 'great pains' to understand the paper and he apologises for delaying the publishing process. He wishes for his anonymity to be preserved. The authors has not grasped the points made by him previously. He thinks 'the more stupid the referee, the more his comments are likely to improve the paper'. [Published in Philosophical Transactions A, 1936]. Endorsed on verso as received 21 August 1935. 18 August 1935