should always be protected by leather or, better still, by
vellum, which is a firmer material--otherwise they will rapidly wear off,
and the boards will break easily at their corners. As to the relative
merits of cloth and paper for the sides of books, cloth is far more
durable, though it costs more. Paper becomes quickly frayed at the edges,
or is liable to peel where pasted on, though it may be renewed at small
expense, and may properly be used except upon the much-read portion of
the library. The cloth or paper should always harmonize in color with the
leather to which it is attached. They need not be the same, but they
should be of similar shade.

One more reason for preferring morocco to other leathers is that you can
always dispense with lettering-pieces or patches in gilding the titles on
the back. All light-colored bindings (including law calf) are open to the
objection that gold lettering is hardly legible upon them. Hence the
necessity of stamping the titles upon darker pieces of leather, which are
fastened to the backs. These lettering-pieces become loose in over-heated
libraries, and tend continually to peel off, entailing the expense of
repairing or re-lettering. Every morocco bound book can be lettered
directly upon the leather. Bock is made of the skin of the Persian sheep,
and is called Persian in London. It is a partially unsuccessful imitation
of morocco, becoming easily abraded, like all the sheep-skin leathers,
and although it is to be had in all colors, and looks fairly handsome for
a time, and is tougher than skiver (or split sheep-skin), the books that
are bound in it will sooner or later become an eyesore upon the shelves.
A skin of Persian leather costs about one-third the price of genuine
morocco, or goat. But the actual saving in binding is in a far less
ratio--the difference being only six to eight cents per volume. It is
really much cheaper to use morocco in the first place, than to undergo
all the risks of deterioration and re-binding.

Of the various imitations of leather, or substitutes for it, we have
leatherette, leather-cloth, duck, fibrette, feltine, and buckram. Buckram
and duck are strong cotton or linen fabricks, made of different colors,
and sometimes figured or embossed to give them somewhat the look of
leather. Hitherto, they are made mostly in England, and I have learned of
no American experience in their favor except the use of stout duck for
covering blank books and binding n