So also medical evidence is often required to ascertain the state of a life on which an annuity may have been granted; where either the gross inadequacy of the price paid, or the exorbitance of the annuity secured, becomes a question for legal determination.[586] SURVIVORSHIP. As the probable duration of human life, under ordinary circumstances, forms the foundation of the system of life insurance, so also does the comparative chance of duration between two or more lives. These contingencies have been made the subject of minute, and we believe accurate calculation.[587] One observation alone is necessary on this branch of the subject: the tables have been constructed on the basis of local mortalities, they must not therefore be considered as universally applicable to all changes of climate and circumstance.[588] A more difficult problem however is presented when it is required to estimate the probable chance that one life had survived another, there being no evidence of the decease of either, though a moral presumption exists of the loss of both. The legal application of this question may arise from a variety of circumstances, as where two or more persons perishing by the same accident, as shipwreck, it is necessary to ascertain the survivor in order to determine the course of succession. This was the case of the representatives of _Gen. Stanwix_, A. D. 1772, (_Fearne’s Posthu. Works, p._ 37) “a case which,” according to the learned author, “seemed to mock every principle of judicial decision.” _Gen. Stanwix_, accompanied by his only child, a daughter by his first marriage, and by his second wife, set sail for Ireland; the vessel was lost and not a single person escaped. If _Gen. Stanwix_ had died a widower, and without issue living at the time of his death, that is to say, if his wife and daughter died before him, though but an instant, _his_ nephew became his representative, and entitled to his personal estate; if the daughter was the survivor, then her personal representative (an uncle) was entitled; and on these claims the principal litigation took place, for though it is evident that the second wife also might have a separate next of kin, and her representative did bring forward a distinct claim, the circumstance is not noticed by _Fearne_ (_see note l. c. p._ 39) “The court, finding the arguments on all sides equally solid and ingenious, waved giving any decision, and advised a compromise, to which the several claimants agreed.” So also in the case of _Col. James_ and his wife, who being passengers in the Grosvenor East Indiaman, were in 1782 cast away on the coast of Africa, and attempted with a great part of the crew and other passengers to make their way to some settlement, but in all human probability perished. In this case there was greater latitude for conjecture than in the preceding, as there was not the same presumption that the fate of both had been nearly cotemporaneous; one might have