A bibliography of English military books up to 1642 and of ...

counting them one by one. It is only necessary to multiply the
number of sets by the number of leaves allotted to each, remembering
that no more than twenty-three letters go to an alphabet.
Thus *, **, in 2% A-CCC in 4% will give two complete alphabets
and three odd letters, besides two signs ; in other words, fortynine
sheets of four leaves each, and two of two leaves—in all, two
hundred.
Many of the foreign books, and especially of the Italian,
are supplied at the end with registers of the signatures, a convenience
which I
have not remarked in any of the English books
consulted.
The form of a book is given throughout according to the
number of leaves to a sheet. As a rule, leaves having the same
signature are taken to belong to the same sheet ;
but sometimes the
wire-lines, combined with the shape and size, show that halfsheets
have been used, or, and this is common in folios, that two
or more sheets have been laid one upon another, or quired, and
then folded, and the whole printed under one signature. A sheet
folded once, with the wire-lines perpendicular, forms a folio ;
folded
twice, with the wire-lines horizontal, it forms a quarto ; and three
times, with the wire-lines restored to the perpendicular, an ocftavo.
The terms in 2*, in 4*, etc., denote the number of leaves allotted
to each signature. It is to be remarked that in the registers
affixed to Italians books the printers sometimes use the corresponding
terms, duerni, quaderni^ etc., when, according to this explanation,
they should say quaderni, ottavi, and so on.
In these cases they are
counting by double leaves, and not by single ; starting from the
folio as being composed of sheets
folded once, giving one double
leaf to a signature, the quarto is described as having two such
leaves, the o6lavo, four. The folio of three sheets quired, giving
as many double leaves to a signature, is said to be in threes {terni).
The abbreviations B.M., Bod., R.U.S.I., etc., denote the
The British Museum is
libraries in which copies are to be found.
rich in early military literature. Of the English books mentioned
in this catalogue, it has all but about twenty, most of the Italian,
and fewer, though still a large number, of the Spanish. Of the
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