From "The Marriage Law of England" James T. Hammick; Secretary of the Registrar General's Office Somerset House; 1873.
"With respect to a person whose husband or wife has been continuously absent for the last seven years, and the fact of whose existance has been unknown to such person during that time, the presumption is that the former consort is no longer living, and that such person is a widower or a widow. As the law allows a person under these circumstances to marry again with impunity, a clergyman would be justified in putting up the banns and celebrating a second marriage.....................At the same time it should always be remembered that a second marriage, while the husband or wife of the first marriage is living is void, and in the event of the return of the absent spouse the ceremony is a mere nullity."
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