Steaming or artificial humidity was the process of injecting steam from boilers into cotton weaving sheds in Lancashire, England, in the late 19th and early 20th centuries. The intention was to prevent breakages in short-staple Indian Surat cotton which was introduced in 1862 during a blockade of American cotton at the time of the American Civil War. There was considerable concern about the health implications of steaming. Believed to cause ill health, this practice became the subject of much campaigning and investigation from the 1880s to the 1920s. A number of Acts of Parliament imposed modifications. Background Warp yarns were strengthened by the addition of size – a substance made from flour and tallow or china clay. High humidity was required to weave sized yarn and to minimise the size dust in the air. This was especially important when cloth companies were forced to use Indian Surat cotton instead of Sea Island cotton from South Carolina in 1862 during the American Civil War. The war occurred at a time of market collapse, and the resulting cotton famine caused speculation and restructuring. American cotton was then subject to a blockade, and although some long staple cotton was grown along the Nile (being called Egyptian cotton), short staple Surat was introduced into the mix in most Lancashire mills. This was far harder to weave; the weavers, who were paid by the piece, at first gladly accepted the artificially induced humidity. Humidity was frequently achieved by injecting steam through pipes into the weaving sheds. The resulting damp conditions caused health risks and considerable discomfort to cotton workers, especially in sheds with poor ventilation. The water was recycled, creating favourable conditions for the propagation of contagious diseases and the accumulation of toxic substances in dyes. Robert Koch discovered the tubercule bacillus in 1882, though the way in which the bacillus was transmitted was not yet understood, allowing the potential question that steaming might be associated with the transmission of tuberculosis. Cotton Cloth Factory Act 1889 The 1887 Annual Report of the Medical Officer of Health for Blackburn, a Dr. Stephenson, referred to the "abominable system of saturating the atmosphere of workshops by means of steam", a practice which he believed led to "the wholesale slaughtering of the inhabitants". During 1889, the Amalgamated Weavers' Association, founded in 1884, campaigned with the Northern Counties Factory Act Reform Association against the practice of steaming. Later that year,