Leaded or art glass is attractive if not overdone. Small panes are difficult to keep clean, of course; but we can probably endure that if all else be equal. In living rooms the upper sash should be made smaller than the lower, so as to get the median rail above the level of the eye. In some parts of the house a horizontal window gives a fine effect, besides affording light and air without affecting privacy. Casement windows have their points of excellence, and are additionally expensive chiefly in hardware. The frames are really cheaper, but they must be very accurately fitted to avoid leaks.

Casement windows seriously complicate the screen and storm-window problem, and expert planning is necessary. The durability of screens depends mostly upon their care or abuse, but if it can be afforded, copper wire will usually last sufficiently longer to repay its additional cost. Metal frames are not so essential. The best form is that which covers the entire window and permits both sashes to be freely opened; but this costs practically twice as much as the half-window screen.