1. Of ascertaining the increment or decrement of the population in every place, and at any period.
2. Of accurately ascertaining the population of the country, and at any period.
3. Of diminishing, if not nearly superseding, the immense expense incurred by a census.
4. Of obviating the difficulties, great expense, and frequent disappointment in proving marriages, births, baptisms, and burials, to which persons who are desirous of establishing legal proof of their identity, descent, consanguinity, &c. are still exposed.
5. The present extensive and beneficial system of assurance on lives, reversionary payments, annuities, and legacy duties on the latter species of testamentary property, is founded on calculations deduced from numerous bills of mortality.
6. The prosperity or decay of commerce, manufactures, or trade of any place, is shown by comparing bills of mortality of different dates.
III. Morally.—They mark:
1. The prevalence of moral or licentious habits.
2. The diseases of which the inhabitants of a place die; and, consequently, those arising from luxury or intemperance.
3. The effects of the passions on human actions.