Flax was once grown in every county of Ireland, when the production of linen was an entirely cottage industry. After the Williamite war of 1691 immigration to Ireland was encouraged and many who came were Huguenots from France. Notably Louis Crommellin came to Lisburn, in County Down, to establish a colony of Huguenot linen weavers. Just how much their arrival contributed to innovation is arguable but they enriched the range of linen idiom. Linen manufacture came to be concentrated in north-west Ulster. Ramazzini, in 1705, had noted respiratory problems associated with ‘a foul mischievous powder’ entering the lungs of flax hacklers, but it was not until production was mechanised in the 19th Century that it became a serious problem. In 1831 Thackrah described similar cases in Leeds; by 1860 Greenhow had employed the term ‘Byssinosis’ (from the Greek ‘bussinos’ – of linen) in an official document and recorded that the condition was exacerbated on Mondays, ie ‘Monday Fever.’ In 1856, Malcolm in Belfast, demonstrated that the condition was related to the initial, dustier phases of linen manufacture. Another Ulster doctor, Charles Nicholas Delacherois Purdon (who had Huguenot forebears), in the 1870s described diseases associated with linen manufacture: ‘…one of the most injurious, and in certain branches very fatal, is the effect induced by the inhaling of flax dust, called by the workers ‘Pouce,’ (from the French: ‘poussif’ – wheezy) which is produced, when the fibre is cleansed by machinery.’ Those employed as ‘doffers’ (from the French: ‘démonteurs’ – dismantlers) who removed the spindles did not suffer from Pouce because they were exposed to heat and vapour rather than dust which rendered them more susceptible to bronchial attacks ‘(Mill Fever).’ Thanks to John Pemberton’s (and others’) research at The Queen’s University of Belfast, Flax Byssinosis became a Prescribed Industrial Disease in 1965.