Copy letter from James Hopwood Jeans, Secretary of the Royal Society; to Sir Dugald Clerk, Chairman of the Applied Sciences Committee and FRS Refers to a paper by W. T. David, 'The internal energy of inflammable mixtures of coal-gas and air after explosions', that Sir Dugald Clerk communicated to the Society. Explains that it has been passed for printing, subject to it being condensed to 'Proceedings' length. Asks Sir Clerk to find out whether the author is willing to make this reduction. 25 November 1920