of Lucifer was working in his brain before the
"tragedy of Cain" was actually begun. He had been recording a "thought"
which had come to him, that "at the very height of human desire and
pleasure, a certain sense of doubt and sorrow"--an _amari aliquid_ which
links the future to the past, and so blots out the present--"mingles
with our bliss," making it of none effect, and, by way of moral or
corollary to his soliloquy, he adds three lines of verse headed,
"Thought for a speech of Lucifer in the Tragedy of _Cain_"--

"Were Death an _Evil_, would _I_ let thee live?
Fool! live as I live--as thy father lives,
And thy son's sons shall live for evermore."

In these three lines, which were not inserted in the play, and in the
preceding "thought," we have the key-note to _Cain_. "Man walketh in a
vain shadow"--a shadow which he can never overtake, the shadow of an
eternally postponed fruition. With a being capable of infinite
satisfaction, he is doomed to realize failure in attainment. In all that
is best and most enjoyable, "the rapturous moment and the placid hour,"
there is a foretaste of "Death the Unknown"! The tragedy of _Manfred_
lies in remorse for the inevitable past; the tragedy of _Cain_, in
revolt against the limitations of the inexorable present.

The investigation of the "sources" of _Cain_ does not lead to any very
definite conclusion (see _Lord Byron's Cain und Seine Quellen_, von
Alfred Schaffner, 1880). He was pleased to call his play "a Mystery,"
and, in his Preface (_vide post_, p. 207), Byron alludes to the Old
Mysteries as "those very profane productions, whether in English,
French, Italian, or Spanish." The first reprint of the _Chester Plays_
was published by the Roxburghe Club in 1818, but Byron's knowledge of
Mystery Plays was probably derived from _Dodsley's Plays_ (ed. 1780, l.,
xxxiii.-xlii.), or from John Stevens's Continuation of Dugdale's
_Monasticon_ (_vide post_, p. 207), or possibly, as Herr Schaffner
suggests, from Warton's _History of English Poetry_, ed. 1871, ii.
222-230. He may, too, have witnessed some belated _Rappresentazione_ of
the Creation and Fall at Ravenna, or in one of the remoter towns or
villages of Italy. There is a superficial resemblance between the
treatment of the actual encounter of Cain and Abel, and the conventional
rendering of the same incident in the _Ludus Coventriae_, and in the
_Mistere du Viel Testament_; but it is unlikely that he had closely
s