Observations on reversionary payments [electronic resource] : on schemes for providing annuities for widows, and for persons in old age; on The Method of Calculating the Values of Assurances on Lives; and on The National Debt. To which are added, four essays On different Subjects in the Doctrine of Life-Annuities and Political Arithmetick. The fourth edition, enlarged into two volumes by additional notes and essays, a collection of new tables, a History of the Sinking Fund, a State of the Public Debts in January 1783, and a Postscript on the Population of the Kingdom. ... . By Richar Price, D.D. F.R.S.