I should have imagined that accusations, concerted by such heads as these, would have vanished of themselves, without any answer; but, since I have the mortification to find that they have been in some degree regarded by men of more knowledge than themselves, I shall explain the motives of my procedure.

My original design was, as I have already explained, to publish a methodical and exact catalogue of this library, upon the plan which has been laid down, as I am informed, by several men of the first rank among the learned.  It was intended by those who undertook the work, to make a very exact disposition of all the subjects, and to give an account of the remarkable differences of the editions, and other peculiarities, which make any book eminently valuable:  and it was imagined, that some improvements might, by pursuing this scheme, be made in literary history.

With this view was the catalogue begun, when the price was fixed upon it in publick advertisements; and it cannot be denied, that such a catalogue would have been willingly purchased by those who understood its use.  But, when a few sheets had been printed, it was discovered, that the scheme was impracticable, without more hands than could be procured, or more time than the necessity of a speedy sale would allow:  the catalogue was, therefore, continued without notes, at least in the greatest part; and, though it was still performed better than those which are daily offered to the publick, fell much below the original design.

It was then no longer proper to insist upon a price; and, therefore, though money was demanded, upon delivery of the catalogue, it was only taken as a pledge that the catalogue was not, as is very frequent, wantonly called for, by those who never intended to peruse it, and I, therefore, promised that it should be taken again in exchange for any book rated at the same value.

It may be still said, that other booksellers give away their catalogues without any such precaution, and that I ought not to make any new or extraordinary demands.  But I hope it will be considered, at how much greater expense my catalogue was drawn up:  and be remembered, that when other booksellers give their catalogues, they give only what will be of no use when their books are sold, and what, if it remained in their hands, they must throw away:  whereas I hope that this catalogue will retain its use, and, consequently, its value, and be sold with the catalogues of the Barberinian and Marckian libraries.

However, to comply with the utmost expectations of the world, I have now published the second part of my catalogue, upon conditions still more commodious for the purchaser, as I intend, that all those who are pleased to receive them at the same price of five shillings a volume, shall be allowed, at any time, within three months after the day of sale, either to return them in exchange for books, or to send them back, and receive their money.