The Queen’s Colleges in Belfast, Cork and Galway were founded in 1845 as a solution to the education of Ireland’s growing middle class, and especially to redress the lack of university education acceptable to Catholics. Chapter One introduces the colleges, as well as placing this dissertation in the context of the literature on history of science and especially history of science in Ireland. Chapter Two presents the Queen’s Colleges as part of a larger project to economically improve the country through practical education for the middle classes, especially in science. It revisits the rejection of the Queen’s Colleges by the Catholic Church and analyses the lasting effects this had on the cultivation of science in Ireland. Despite the controversy, the colleges opened in 1849 and the rest of the dissertation considers what the colleges were able to achieve in terms of science. Chapter Three focuses on Cork, where the local scientific societies had been integral in the placing of a college in that town. These societies now courted the professors as members, acting as a means of entrée into the social community and altering their activities as a result of the professors’ participation. The agriculture diploma offered in the colleges was expected to have the greatest practical impact on Ireland by encouraging the application of science to farming. Chapter Four examines the unexpected failure of this project due to competition with other similar community initiatives and an inability to balance both practical and scientific concerns. Chapter Five discusses the college museums, which sought, through the collection of objects from across the British empire, to be national (not simply local) institutions for public education and the improvement of Ireland. The final chapter turns to the scientific community itself in an account of the controversy over Eozoön Canadense, believed to be the oldest fossil organism. Two Galway professors harnessed an invisible scientific community through letters and publication in an effort to resolve the controversy in their favour. The Eozoön controversy demonstrates that peripheral locations should not be disregarded as centres of scientific activity and further shows the links between local communities of science and an international scientific community. This dissertation argues that the Queen’s Colleges were integral to the shaping of science in Ireland in the second half of the nineteenth century. While provincial Ireland had a scientific culture of its own before the colleges arrived, the colleges brought government-appointed experts to local communities. The college professors encouraged the growth of expert science in Cork’s scientific societies, presented British-style scientific collections to the Irish public, attempted to alter farming in Belfast to conform with scientific principles and brought an international scientific controversy to remotest Galway. Existing communities of science, and those now created by the presence of the colleges had to negotiate new roles within the scientific culture of Ireland and Britain.