In larger libraries there are various kinds used. Airtight, non-opening windows have been advocated for stacks, to exclude dust and drafts (the windows in the Library of Congress stack are of this kind), but they are not much favored. French windows, pivoted at the side, or long windows pivoted in the middle at top and bottom, will admit air freely in summer. There are various patented devices to hold a pivoted window open just so far as may be desired.
Really the whole matter is for the architect, with the librarian’s advice as to what is most wanted in each room. Light always, clear light, which usually precludes stained glass, but may demand translucent or prismatic glass. Ventilation, perhaps, which requires some way of opening the whole or part of the window. Easy cleansing always, which also requires ready opening, or a balcony outside. Due protection against fire, which requires wire-glass.
All windows in reading rooms should run up clear to the ceiling, for ventilation, and because top light penetrates further. “One square foot of glass near the ceiling admits as much light as ten near the floor. Pointed Gothic windows are bad.”—Burgoyne.[203] For the latter reason, all windows in reading rooms should be square-topped (which shuts out the Gothic style), and not overhung by eyebrows, nor should they have thick sashes, bars, leads or mullions, which hamper light. Leaded glass, especially in diamond or lozenge forms, is hard to clean. Clear, large panes of good plate glass are best. Study use rather than ornament everywhere, but most in windows.
These suggestions as to school rooms might apply to libraries:—
“The top of the windows is placed as near the ceiling as the finial will admit. Transom bars should not be permitted.”—Sturgis.[204]
“Large sheets of glass rather than the art filagree work so often used, which obstructs fifty per cent of the light,”—Burgoyne.[205]
With these essentials in mind look at the illustrations under this head, or passim, in Sturgis’s Dictionary of Architecture, and see how few of the picturesque windows there could be used for any reading or administration room of a modern library. Either pointed or overhanging tops, or heavy frames, or transoms, or mullions, or traceries, or leaded panes, must be barred out by the architect who designs libraries.
High or Low. If the windows must run to the ceiling, they have to be high. How long they are to be, how low they extend, depends on the height of the story and whether or not wall shelving is wanted below them. If the library has more than one story and has a stack to limit the height of stories to fourteen or fifteen feet, shelves all round the wall will be wanted in many of the rooms. The shelves at extreme height should only be eight feet to top of cornice, or could be any less height, down to about four feet, that the exigencies require. The window can take up as much of the remaining height of wall as needs of lighting demand. This leaves some alternatives of length and width for the architect in arranging his exterior.
High windows above wall shelving are much used, as exterior views will show. One consideration has occurred to me, which I have not seen mentioned. In libraries where there is no window low enough to jump out of, and only one entrance on a floor, where is the extra fire escape usually demanded by municipal building regulations?
High or Low for View. Some objection has been made recently to high window sills in a library because only low sills allow a cheerful outlook. I just put the alternative to a working girl, as a typical user, and she said, “How could I read if I was watching a squirrel?” This seems to put the matter in a nut-shell. Library windows are for light, not for sight. In private libraries or in clubs, the cosy comfort idea can come uppermost, but in the more practical rooms, especially in reading rooms chiefly for reference use and study, I should get diffused cheer, so to speak, from diffused light, and bar looking out of the window. As to the working rooms, much the same view might be taken, but if a librarian or a cataloguer pleaded for low sills and a cheery outlook, I might consider the “personal equation,” and concede it.