Dictionary of National Biography, 1885-1900/Milne, Joshua
MILNE, JOSHUA (1776–1851), actuary, born in 1776, was appointed actuary to the Sun Life Assurance Society on 15 June 1810. His great knowledge of mathematics well qualified him for the reconstruction of the life tables then in use, which were based upon the table deduced by Dr. Richard Price from the burial registers (1735–80) of All Saints' Church, Northampton. Milne took as the basis of his calculations the Carlisle bills of mortality, which had been prepared by Dr. John Heysham, and after a long correspondence (12 Sept. 1812-14 June 1814) with Heysham he published his famous work, ‘A Treatise on the Valuation of Annuities and Assurances on Lives and Survivorships; on the Construction of Tables of Mortality; and on the Probabilities and Expectations of Life,’ &c., London, 1815, 2 vols. 8vo. The result was a revolution in actuarial science. Milne's table, which, considering the narrow data from which he had to work, was remarkably accurate, was very generally adopted by insurance societies, and subsequent writers have been greatly indebted to his investigations.
Milne was the first to compute with accuracy, though with unnecessary complexity, the value of fines, and his notation for the expression of life contingencies suggested that afterwards adopted by Augustus De Morgan in his ‘Essay on Probabilities.’ His book may still be read with profit. Milne could never be induced to revise his algebraical calculations, although they to some extent marred by their complexity the usefulness of his work. He gave evidence before the select committee on the laws respecting friendly societies (1825 and 1827), but long before his death he appears to have abandoned the subject with which his name is identified. ‘I am far from taking an interest now,’ he wrote to Augustus De Morgan (May 1839), ‘in investigations of the values of life contingencies. I have long since had too much of that, and been desirous of prosecuting inquiries into the phenomena of nature, which I have always regarded with intense interest.’ He had an ‘unusually minute’ knowledge of natural history, and is said to have possessed one of the best botanical libraries in London. He resigned his position in the Sun Life Office, owing to growing weakness, on 19 Dec. 1843, and died at Upper Clapton on 4 Jan. 1851.
In addition to the work mentioned above he contributed to the ‘Encyclopædia Britannica,’ 4th edit., articles on ‘Annuities,’ ‘Bills of Mortality,’ and ‘Law of Mortality.’ The last was reprinted in 1827 (Report from the Select Committee on the Laws respecting Friendly Societies, 1827, App. G 3), together with a valuable statement on the Carlisle and Northampton tables of mortality (ib. App. B). The Carlisle table was largely superseded by that published by the Institute of Actuaries in 1870.