[Illustration: PLATE XLIV.--Window and Shutters, Free Quakers' Meeting House, Fifth and Arch Streets; Second Story Window, Free Quakers' Meeting House.] [Illustration: PLATE XLV.--Detail of Windows, Combes Alley; Window and Shutters, Cliveden; Window, Bartram House.] As to the doors themselves, four distinct types were common throughout the Colonial period. Single and double doors were equally popular, high, narrow double doors being favored for the more pretentious houses, although instances are not lacking of single doors in the mansions of Colonial times. With very few exceptions molded and raised panels with broad bevels were used in all, and it is according to the arrangement of these panels that the different types of doors are best classified. One of the earliest and simplest was the six-panel single door with three stiles of about equal width, top and frieze rail about the same, bottom rail somewhat wider and lock rail about double the width of the frieze rail. The upper pair of panels were not quite high enough to be square, while the middle and lower pairs were oblong in shape, the middle one being higher than the lower. Rarely this relation was reversed, and the lower pair was higher than the middle pair, the door at Number 6504 Germantown Avenue being an example. As found in the farmhouses of Germantown and thereabouts, notably Wyck, Glen Fern, the Green Tree Inn and the Johnson and Billmeyer houses, these six-panel doors were split horizontally through the lock rail, dividing them into an upper and lower part. This arrangement made it possible to open the upper part for ventilation while keeping the lower part closed to prevent stray animals and fowls from entering the house. Numerous examples of undivided six-panel doors are shown by accompanying illustrations and referred to in detail in succeeding paragraphs. Of these the door of Grumblethorpe is unique in having a double stile in the middle, giving almost the appearance of double doors. Three-panel double doors, such as those of Mount Pleasant, Solitude and Port Royal House, were less common than any of the four principal types mentioned, and were little used except for a few decades after the middle of the eighteenth century. Like six-panel single doors, the upper panel was often almost square, and the middle oblong panel higher than the bottom one of the same shape. At Mount Pleasant the middle and lower panels were of the same size.