t 3'9 3 
live between 
Thofe whofe Ages together are 40 24 and 2 5 Years. 
- - - - 50 22 and 2 3 . 
60 23 and 21. 
70 19 and 20. 
80 17 and 1 8. 
- _ - - - - - - 90 1 4 and 15. 
100 12 and 1 3. 
And finifhes with reje&ing the Method of calculating 
the Quantity of People after the manner of Voffius, 
Auzont , Petty x and others. — - - 
... ; ■ \ \ . •; - 
Third Tart, 
The Third Treatifc contains, 1/?, A Copy of a 
Letter wrote by the Author in the Beginning of the 
Year 1741, to the worthy Mr. yohn Eames , one of 
the Fellows of this Honourable Society, and laid 
before the fame foon after, by the faid Gentleman. 
zdly, A Demonftration, in 29 Tables, that Mr.' 
Simpforis Calculation of Lives, as 1 to 26, is a Mis- 
take, and his own Hypothefis, as 1 to 35, right 5 and 
proves from Mr. Maitland’s Obfervations, Page 541. 
that Children in London, of Two Years old, continue 
to live, on a Medium, above 37 Years ; and obferves, 
that the Learned Dr. Halleys Table has it full 38 
Years and a half. 
The Author fuppofes, 3 dly, That out of every, 
100 Children born. Five come dead into the World 
and that out of every 100 Children born alive, near 
2 c 'die under a Year old ; and fhews, 4 thly, how 
much Mr. Simpfon differs in his Calculation; — 
namely. That full 3 2, out of 100 Children, die, under i 
a Year old.-— 
The 
