ON THE STATISTICAL VIEW OF NATURE. 565 



was easy ; the invention was the difficulty. The 

 next great name connected with this subject was 

 the astronomer and mathematician Edmund Halley, 1 

 who had before him, in addition to John Graunt's 

 work, the figures of birth and mortality during 

 the five years 1686 to 1691 collected by Kaspar 

 Neumann for the city of Breslau, capital of the 

 province of Silesia. Tables of mortality, based upon 

 several thousands of life annuities, were prepared in 

 Holland by order of the Grand Pensioner, John de 

 Witt, and used in 1671 as the basis for a loan in 

 the form of annuities. 2 The growing practice of 

 life insurance, as is well known, attaches a great 

 interest to these tables of mortality, which have been 

 slowly perfected in the course of the last hundred 

 and fifty years ; it having been reserved for the labours 



1 For a long time it was not 

 known how Halley came into 

 possession of Kaspar Neumann's 

 mortality - tables ; but, in recent 

 times, mainly through examination 

 of the local records of the city of 

 Breslau by Bergius and others, and 

 notably by the aid of S. Gratzer 

 (' Edmund Halley und Kaspar 

 Neumann,' Breslau, 1883), it has 

 become almost certain that Neu- 

 mann's registers were communi- 

 cated to the Royal Society by no 

 less a person than Leibniz, who 

 corresponded with Neumann on 

 the one side as well as with the 

 secretaries of the Royal Society on 

 the other. Some of the original 

 documents have been traced in 

 the archives of the Society by Dr 

 Bond and Prof. Burdon Sanderson. 

 It is well known that Leibniz him- 

 self attached great importance to 

 accurate statistical knowledge of 



all kinds, and considered the collec- 

 tion of such to be one of the main 

 duties of the various academies 

 which he planned or founded. 



2 " Le grand pensionnaire de 

 Hollande, Jean de Witt, se fondant 

 sur les calculs de probability's en- 

 seigne"s par Chretien Huygens, se 

 servit, comme elements d'observa- 

 tion, des resultats constates sur 

 quelques milliers de rentiers via- 

 gers. II presenta sa table aux 

 e"tats ge'ne'raux le 25 avril 1671, 

 pour servir de base b, un emprunt 

 fait sous la forme d'annuites via- 

 geres. Cette table citee par M. de 

 Baumhauer, se trouve dans les 

 registres des e"tats de Hollande, 

 annee 1671 " (Block, loc. cit., p. 

 196). A translation of this docu- 

 ment appeared in ' Contributions 

 to the History of Insurance ' by F. 

 Hendriks, 'Ass. Mag.,' vol. ii., 1852. 



