Of those of the Prince Society, the
Grolier Club, and others in America, only from 150 to 300 copies were
printed, being for subscribers only. Rarity and enhanced prices
necessarily result in all these cases. Of some books, only five to ten
copies have been printed, or else, out of fifty or more printed, all but
a very few have been ruthlessly destroyed, in order to give a fanciful
value to the remainder. In these extreme instances, the rarity commonly
constitutes almost the sole value of the work.

(2) Even where many copies have been printed, the destruction of the
greater part of the edition has rendered the book very rare. Printing
offices and book binderies are peculiarly subject to fires, and many
editions have thus been consumed before more than a few copies have been
issued. The great theological libraries edited by the Abbe J. P. Migne,
the _Patrologie Grecque, et Latine_, owe their scarcity and advanced
prices to a fire which consumed the entire remainder of the edition. All
the copies of a large edition of "Twenty years among our savage Indians,"
by J. L. Humfreville, were destroyed by fire in a Hartford printing
office in 1899, except two, which had been deposited in the Library of
Congress, to secure the copyright. The whole edition of the _Machina
coelestis_ of Hevelius was burned, except the few copies which the author
had presented to friends before the fire occurred. The earlier issues in
Spanish of the Mexican and Peruvian presses prior to 1600 are exceedingly
rare. And editions of books printed at places in the United States where
no books are now published are sought for their imprint alone and seldom
found.

(3) Many books have become rare because proscribed and in part destroyed
by governmental or ecclesiastical authority. This applies more especially
to the ages that succeeded the application of printing to the art of
multiplying books. The freedom of many writers upon politics and popular
rights led to the suppression of their books by kings, emperors or
parliaments. At the same time, books of church history or doctrinal
theology which departed, in however slight a degree, from the standard of
faith proclaimed by the church, were put in the Index Expurgatorius, or
list of works condemned in whole or in part as heretical and unlawful to
be read. A long and melancholy record of such proscriptions, civil and
ecclesiastical, is found in Gabriel Peignot's two volumes--_Dictionnaire
des livres condamn