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star.arm.ac.uk/history/architecture.html
Description:
To the casual observer, the small, picturesque Observatory at Armagh looks not dissimilar to many other country houses in Ireland of the late 18th century. It has a square, rather sparsely ornamented Georgian residence connected by a low wing to an eastern tower. However, on closer inspection, one becomes aware of a building with a number of rare, if not unique, features and one that tells us not only something of its architect, Francis Johnston, but also something of the history of astronomy over the past two hundred years. To understand and appreciate its architectural features it is necessary to know something of the types of building constructed for making astronomical observations in the 18th century in other parts of Europe.
