Page:The Construction of the Wonderful Canon of Logarithms.djvu/128

104 PRELIMINARY. are added particulars of the Logarithmic tables computed by Ursinus, Kepler, and Briggs, with a note of some other works of interest.

The arrangement of the title-page in the original is indicated by placing an upright bar to mark the end of each line.

The symbols 4°, 8°, 12°, etc., indicate the number of leaves into which the sheet of paper was folded; but the number of leaves made up in the signatures sometimes differs from this: thus, for example, in the early editions of A Plaine Discovery, though the sheet is folded into 4 there are 8 leaves to each signature.

The measurement of the largest copy examined has been given, but in many cases the work in its original state must have been considerably larger, the copy having been cut down in rebinding.

The signatures in the editions described consist of the letters of the alphabet excluding J, U, and W, or 23 letters (in one or two instances J and U are used for I and V). To each letter belongs a bundle of leaves, 4, 8, 12, &c., as the case may be. The leaves in each bundle are usually numbered thus :&mdash;C, C$2$, C$3$, etc., but frequently the signatures are printed only on the first one or two leaves in each bundle. The signature is very rarely printed on a title-page. When a leaf is described as B$3$, for instance, both sides are included, B$3$$1$ being used to signify the recto and B$3$$2$ the verso.

To each entry in the Catalogue, under the head of Libraries, is appended a note of the principal public libraries in this country which possess copies, to these the names of a few foreign libraries are added. The following abbreviations are employed:&mdash;

Un. Ed.