By the mid-19th century about 200,000 miners were employed in a UK coal mining industry still growing with the advances of the Industrial Revolution. Coal miners were long known to suffer poor health but the link to inhaling dust in the mines had not been made. In 1813 George Pearson was the rst to suggest that darkening of lungs seen in normal individuals as they aged was caused by inhaled soot from burning oil, candles and coal, which were the common domestic sources of heat and light. In 1831 Dr James Craufurd Gregory rst described black pigmentation and disease in the lungs of a deceased coal miner and linked this to pulmonary accumulation of coal mine dust. Gregory hypothesised that the black material seen at autopsy in the collier's lungs was inhaled coal dust and this was con rmed by chemical analysis carried out by Professor Sir Robert Christison. Gregory suggested that coal dust was the cause of the disease and warned physicians in mining areas to be vigilant for the disease. This rst description of what came to be known as 'coal worker's pneumoconiosis' sparked a remarkable intellectual effort by physicians in Scotland, culminating in a large body of published work that led to the rst understandings of this disease and its link to coalblackened lungs. This paper sets out the history of the role of Scottish physicians in gaining this understanding of coal worker's pneumoconiosis. It describes Gregory's case and the lung -recently discovered in the pathology collection of the Surgeons' Hall Museums, Edinburgh, where it has lain unnoticed for over 180 years -on which Gregory based his landmark paper.