in two directions. One springs primarily from Graunt, flows through Petty's Essays, and leads, as has already been said, to modern vital statistics: the other proceeds from Petty's Political Arithmetick through Davenant and Gregory King to Arthur Young and Chalmers. It has perhaps affected even Sir Robert Giffen. Parallel with it goes the development of the German Universitäts-statistik from Conring to Achenwall and Schlözer, whose relations to English political arithmetic have not been fully worked out. So far as I can see, the German discipline was at no time superior to the English in any respect save in the possession of the name "statistics." And Knies has forced it to yield up that.
In the field of vital statistics the connection from Graunt to Süssmilch can be traced without a break. The extent to which Petty's Essays depend upon Graunt has been noted already. The next link in the chain is Edmund Halley's Estimate of the Degrees of Mortality of Mankind, which was published in 1693 in the Philosophical Transactions of the Royal Society. From this paper springs modern life insurance. It cannot be doubted that Caspar Neumann materially assisted Halley by furnishing him figures for a stationary population from the Breslau bills, and it seems clear that Halley's suggestions were less esteemed in England than in Germany in the years immediately succeeding their publication.[1] It is nevertheless true that Halley published the first real life table, and that he mentions at the outset of his paper the prior work done upon the bills of mortality by Petty and Graunt. After Halley the next writer who acknowledges his indebtedness to them is the Rev. William Derham (1657-1735), who was also a member of the Royal Society. Derham was appointed to lecture upon the famous Boyle foundation for proving the Christian religion against atheists, deists, pagans, Jews, and Mohammedans; and, as became a scien-
- ↑ Cf. J. Gratzer, E. Halley und Caspar Neumann, 1883.