(9) The old-fashioned ledge is not needed, except in a few instances. It unnecessarily widens the aisle above, interfering with close storage. Wide books can be stored elsewhere; and space to lay books down in handling can be provided near by.
(10) The average dimensions of shelves[258] are well settled by custom; e.g., Length (as above), not over three feet; Depth, eight inches, except for special sizes of books (see later); Thickness; for wooden shelves, ⅞ inch finished, (1 inch stuff, planed); Interval, Wood or metal 10 inches (11 inches top to top of wooden shelves) for octavos and duodecimos, though one advantage of movable shelves is the possibility of variation if desired anywhere.
(11) No doors of any kind are used in modern library bookcases, except where dust is to be excluded from delicate books, or thieves are to be excluded from rare books. Doors are an impediment to use.
Shelf-bases. To save books in sweeping, a four-inch solid base is usually provided in all lands of shelving. In unusually high shelves, this base projects as a step, but it is unsightly thus, and just so much as it projects it narrows the aisles and promotes stumbling.
See Fletcher, Public Libraries.[259]
Fixed or Movable. As stated above, fixed shelving is somewhat cheaper and more easily made, and will serve well in very small libraries. In setting up movable shelving a row of shallow holes an inch apart is bored an inch from the front and from the rear edge of the inside uprights. To support the shelves, projecting pegs of various kinds are inserted in these holes at any desired intervals. There are several patents, the most popular one being a metallic pin with shoulder, which may be turned over for slight alteration of interval. Plain picture screw-eyes, with the eyes turned flat, are favorites in some libraries, and are cheap. Accuracy is necessary in boring the holes, and experiments are advisable as to the fit and steadiness of the pins, so that the shelves will not be liable to tip or fall.
Wood or Metal. In small libraries there is no need at all of metallic cases or shelving and it is absurdly wasteful to buy them too soon. Wooden shelving is cheaper, easier put up by local builders, and though it may occupy a trifle more space, is serviceable and strong enough until superimposed stories of shelving become necessary. Even two stories of wood can be easily managed. If you want more than two stories to use as a stack, you must have iron or steel. There are, of course, many advantages in metal when you have to come to it, though it is more costly. It saves a certain amount of space; it does not obstruct light or ventilation so much as thicker material; it is more fireproof; shelves are more easily moved.
Metal in stacks is universal in larger libraries in America, so is wood in small libraries. In England wood seems much more used in large libraries than with us.
Hard wood is not necessary for shelving, the cheaper kinds of soft wood will do, and are easier set. No backing is necessary in any form of book case, except as a brace, or for appearance, or against a brick or stone wall.
“Use no paint, but varnish and rub thoroughly.”—Poole.[260]