The architecture of the window naturally plays an important part in the determination of curtain treatment. Where the wall beneath the window is recessed as well as is the window itself, the obvious suggestion is that the curtains should be long. It is undeniable that in handsome apartments rich curtains sweeping over the floor give an opulence of appearance, but for reasons of cleanliness it is certainly better that they should escape the floor by an inch or so.

Where the window only is recessed and the cill has a pronounced extension, curtains of cill length are naturally indicated. A slight cill extension is no obstacle to long curtains if desired, as the curtain flows gracefully over it. Even if a radiator or piece of furniture, such as a dressing-table, occupies the central portion of the window, long curtains may still be used, hanging straight at the sides and not being drawn (Plate 82 B).

Thin curtains have usually been made of cill length, but if this is done the draught takes them out of the window immediately the sash is raised, and they become soiled. Furthermore, thin curtains must be carefully placed on. stretchers when laundered or they will shrink till they no longer reach the cill. Another objection is that where there is no furniture below the window cill-length curtains give a "boxed-in" appearance. A better plan, therefore, is to have these curtains extend slightly below the woodwork under the window - how much depends upon convenience and proportion. Where two pairs of curtains are used, it is customary to have the thin pair short whether the coloured pair be short or long.

The most usual plan where there are over-curtains and valance is to have them cover the window casings, but unless these are bad in style, condition or colour there is no reason why this arrangement should prevail, and there is a valid objection to it which seems to have been universally overlooked. Where curtains cover the woodwork they naturally stand out somewhat further beyond it, so that the general effect is the projection of the outline of the window into the room, while the feeling should be that a window is recessed. If, therefore, the exceptional circumstances mentioned above do not exist, it is preferable that over-curtains be contained within the casing. The rod is then run across slightly back of the fore edge of the woodwork and the valance placed in front of it but still within the casing (Plate 85). When the curtains are translucent or transparent there is still greater reason for this arrangement, as if they were placed over the outside woodwork this would show through and the result would probably be disagreeable.

Another advantage of the showing of the woodwork where it is good, is the preservation of architectural lines.

If, because of ugliness, it is found better to hide the casing, opaque curtains should be used. By the same means much may be done in remedying defects of size or proportion. If the window is noticeably small for the room, the setting out of such curtains somewhat along the side wall and the raising of the top of the valance above the framework will naturally increase its apparent size. If high and narrow, the curtains may be set out at the sides and a deep valance employed (reducing the apparent height), the head of the latter then being set even with the top of the casing. If a window is low a valance had better be omitted, or confined to a narrow strip merely to carry the colour across.

For a deeply recessed bow with three or more windows there are two most attractive treatments, both of which are illustrated:

I. A valance run across the front of the alcove, and curtains to the floor at each side, these being of heavy and rich material. Light silk or casement-cloth short curtains of a different but harmonising colour at the windows themselves. (See Frontispiece.)

IL Long curtains at the two sides of the bow, valance following the tops of the windows with short curtains (Plate 84 B).

Ranges of casement windows, so frequent in Tudor houses, are treated in this same manner without the long curtains.

For double and triple windows but slightly recessed with cill straight across, it is best to run a long rod straight across the front, from which hang side and dividing curtains all of the same length, to the cill, below the woodwork, or full length, as will give the best appearance under the existing conditions. To these a valance may be added.