Third referee's report by Robert Robertson, on a paper 'Estimation of the combustion products from the cylinder of the petrol engine and its relation to "knock"' by Alfred Charles Glyn Egerton, F Ll Smith and Alfred Rene Jean Paul Ubbelohde Sectional Committee: Chemistry No clear statement regarding publication in the 'Philosophical Transactions of the Royal Society'. The presentation of the combined papers is better, but 'the sequence of the chemical work is not always easy to follow'. 'It seems to me a pity that in the summary the conclusions arrived at in Part V are not given in some concise manner. I fancy I have noted in summaries accompanying papers recently that instead of the author clearly stating his views he refers to a discussion. This does not help either the busy man or the expert who wants to use these summaries'. [Published in the Philosophical Transactions of the Royal Society] Endorsed on verso as received 5 February 1935. 4 February 1935