Letter from Norman Bailey, on a paper 'Spectral theory for the differential equations of simple birth and death processes' by W Ledermann and G E H Reuter, to D C Martin Paper reference code: A210 Bailey remarks the paper is valuable, suggests the authors may like to mention 'equations that raise for moments on cumulants, which always constitute an infinite set, even when the probability equations are a finite system', and comments he has not had the time to check all mathematical details. Written at Investigation into the Functions and Design of Hospitals, Nuffield Lodge, Regent's Park, London [England]. [Published in Philosophical Transactions A, 1954]. Endorsed on recto as received 23 June 1953. 22 June 1953