630 PHILOSOPHICAL TRANSACTIONS. [anNO 1742-3. 



1738 inclusive, there have been buried in this city 7323 persons annually (Jews 

 excepted) ; and there having been married, during the same time of 43 years, 

 2311 couple annually, produced, according to the author's computation, 7134 

 children annually, at a medium ; and takes it thence for certain, that Amster- 

 dam contains (including 20000 Jews, as observed in his first treatise, p. 21) 

 241000 souls. — The author proceeds, in the like manner, about other places. 

 He then gives a table showing how long 432 widows lived during a century, 

 and finds it to have been near 14 years each on a medium ; and then subjoins 

 a list how many years married people of different ages continue to live probably 

 together, before the bonds of matrimony, by the death of either party, are dis- 

 solved ; namely, 



live between 



Those whose ages together are 40 . . 24 and 25 years. 



30 . . 22 and 23. 



60 . . 20 and 21. 



70.. 19and20. 



80.. 17 and 18. 



go.. 14 and 15. 



100.. 12 and 13. 



And finishes with rejecting the method of calculating the quantity of people 

 after the manner of Vossius, Auzout, Petty, and others. 



The third treatise contains, 1 st, A copy of a letter written by the author 

 in the beginning of the year 1741, to Mr. John Eames, F. R. S. 2dly, A de- 

 monstration, in 29 tables, that Mr. Simpson's calculation of lives, as 1 to 26, 

 is a mistake, and his own hypothesis, as 1 to 35, right ; and proves, from Mr. 

 Maitland's Observations, that children in London, of 2 years old, continue to 

 live, on a medium, above 37 years ; and observes, that Dr. Halley's table has it 

 full 38 years and a half. 



The author supposes, 3dly, That out of every lOO children born, 5 come 

 dead into the world; and that out of every 100 children born alive, near 20 

 die under a year old ; and he shows, 4thly, how much Mr. Simpson differs in 

 his calculation; namely. That full 32, out of 100 children, die under a 

 year old. 



The rest of this treatise consists in divers calculations and tables of interest, 

 and the value of annuities for life on different ages and interest ; and concludes 

 with an explanation of the same, and the usefulness thereof. 



