The great cathedrals of the Middle Ages during the Gothic period of ecclesiastical architecture formed the inspiration for this particular architectural style; not only in residential buildings, but in many commercial structures, churches and cathedrals built during this time. St. Paul's and St. Patrick's Cathedrals in Melbourne are excellent examples of the Gothic Revival period, often referred to as Victorian Gothic. Characteristics were: steeply pitched roofs often made of slate, narrow doors and windows resolving in a Gothic pointed arch at their height (known as lancet windows), diamond pane glazing to windows imitating a stained glass affect, and intricate parapets, often of a religious nature, with a cross. In non-terrace houses, the drawing room was often pulled forward, adding a bay window to the front of the dwelling.