302 Dr. Young's formula for expressing 
x being the age of the person, which is nearly true between 
20 and 70, the annual mortality must be expressed by 
? ? - '° 66 : a fraction which at 20 becomes — ,at4o, at 
6o ’ TT> anc ^ at 8o > T7 • O ur ta ^ e gives respectively T ; 
f , and f- : the Northampton — , f, — , and — . Mr. FIN- 
23 7-3 r 7 1 48 25’ 7.4 
laison's male annuitants -f, — , — , and f-. The healthiness 
87’ 73 3 2 8.3 
of Mr. Finlaison's annuitants about 40 and 50 is one of the 
most remarkable features of his table: he observes (p. 58), 
that out of 10,000 persons at 23, 141 will die in a year, and 
141 will die out of the same number at the age of 48 ; but at 
the age of 34 there will only die 124. The curve marked by 
obelisks, +,in the diagram, will show the comparative pro- 
gress of mortality in this system ; which, however valuable 
the data may be, appears to exhibit too many novelties, if not 
anomalies, to be generally adopted with confidence : while 
the line of crosses, x, representing the tontine of Depar- 
cieux, will serve to show how little difference the lapse of a 
century has made in the results of these two similar cases. 
I shall conclude, my dear Sir, with a comparison of the 
climacteric years, as they may be called without impro- 
priety, in which the greatest numbers of adults die, as taken 
from different tables. 
I sincerely hope that these considerations may help to un- 
deceive the too credulous public, who have of late not only 
received some hints that tend to insinuate the probability of 
an occasional recurrence of a patriarchal longevity, but who 
have been required to believe, upon the authority of a most 
respectable mathematician, that the true and unerring value 
