The Steam Engine Makers' Society (SEM), and early national engineering trade union, recorded each payment of its sickness benefit to individual members, and also listed all members each year. Nominal linkage techniques have been used to reconstruct individual histories of absence from work due to sickness from these data, link the resultant histories to records of members' funerals, and then in some cases further link them to a man's death certificate, obtained from the civil registration system. These individual histories are then used to analyse variations in both sickness rates and the duration of illness by age, season, and the state of the economy, for the years 1836 to 1845. The individual death certificates and comparative data on mortality for different occupations are used to draw some conclusions concerning the causes of ill-health among these men. Relating morbidity to mortality for specific individuals, there is an unsurprising relationship between consumptive diseases and extended prior sickness.