o of 1623, yet we feel reasonably certain from this entry that
this play must have been written either {76} in 1608 or earlier. In
addition to the record of the Stationers' Register, we have the dates
on the title-pages of such plays as appeared in Quarto. These
evidences, it must be remembered, determine only the latest possible
date for the play, as many were written long before they were printed,
or even entered.

Again, other men sometimes used in their books expressions borrowed
from Shakespeare or remarks which sound like allusions to something of
his. Here, if we know the date of the other man's book, we learn that
the play of Shakespeare from which he borrowed must have been in
existence before that date. Thus, when the poet Barksted prints a poem
in 1607 and borrows a passage in it from _Measure for Measure_, we
conclude that _Measure for Measure_ must have been produced before
1607, or Barksted could not have copied from it. This form of evidence
has its dangers, since occasionally we cannot tell whether Shakespeare
borrowed from the other man or the other man from him; nevertheless it
is often valuable.

Furthermore, we sometimes find in contemporary books or papers, which
are dated, an account of the acting of some play. A law student named
John Manningham left a diary in which he records that on February 2,
1602 he saw a play called _Twelfth Night or What You Will_ in the Hall
of the Middle Temple; and his account of the play shows that it was
Shakespeare's. Dr. Simon Forman, in a similar diary, describes the
performance of three Shakespearean plays, two of the accounts being
dated. Still more important in this class is the famous allusion,
already quoted, by Francis Meres in his _Palladis Tamia_, a {77} book
published in 1598. In this he mentions with high praise six comedies
of Shakespeare: _The Two Gentlemen of Verona_, _The Comedy of Errors_,
_Love's Labour's Lost_, _Love's Labour's Won_,[1] _A Midsummer Night's
Dream_, and _The Merchant of Venice_; and six "tragedies": _Richard
II_, _Richard III_, _Henry IV_, _King John_, _Titus Andronicus_, and
_Romeo and Juliet_.[2] Hence, we know that all these plays were written
and acted somewhere before 1598, although three of them did not appear
in print until 1623.

The above list does not exhaust all the forms of external evidence, but
merely shows its general nature. External evidence, as can be seen, is
not something mysterious and peculiar, but