The Collaborative International Dictionary of English v.0.48:
Herself \Her*self"\, pron.
1. An emphasized form of the third person feminine pronoun;
-- used as a subject with she; as, she herself will bear
the blame; also used alone in the predicate, either in the
nominative or objective case; as, it is herself; she
blames herself.
[1913 Webster]
2. Her own proper, true, or real character; hence, her right,
or sane, mind; as, the woman was deranged, but she is now
herself again; she has come to herself.
[1913 Webster]
By herself, alone; apart; unaccompanied.
[1913 Webster]