Most environmental conflicts created by the industrial revolution were solved by industries paying indemnities to their adjoining communities. How did air and water – which were major determinants of health according to neohippocratic medicine – become the objects of financial transactions? To characterise this great transformation, I study the regulation of workshop conditions by local police and parliaments of the Ancien Régime. Then, I underline the role of hygiene and the chemical revolution (the quantification of matter and the industrialisation of manufacturing processes) in the rise of a liberal regime of environmental regulation.