500 Chandler—The Inter’Generation Period , 
A 
B 
I 
1 
1637 
I 
2 
1616 
... 
II 
5 
1677 
40 
II 
13 
1651 
35 
... 
III 
24 
1712 
35 
III 
24 
1696 
45 
... 
IV 
40 
1741 
29 
104 
IV 
52 
1720 
24 
104 
V 
105 
1774 
33 
97 
V 
150 
1757 
37 
106 
VI 
236 
1810 
36 
98 
VI 
231 
1798 
41 
102 
VII 
460 
1844 
34 
103 
VII 
387 
1829 
31 
109 
VIII 
397 
1870 
26 
96 
VIII 
534 
1856 
27 
99 
1268 
1393 
Mean period, 
33.3 
a 
Mean period, 34.3 
Omitting generation VIII, 
34.5 i 
Omitting generation VIII, 
35.5 
C 
D 
I 
1 
1635 
.. 
I 
5 
1632 
.. 
... 
II 
8 
1667 
32 
II 
44 
1665 
33 
... 
III 
44 
1700 
33 
III 
147 
1702 
37 
... 
IV 
81 
1743 
43 
108 
IV 
467 
1737 
35 
105 
V 
257 
1782 
39 
115 
V 
783 
1771 
34 
106 
VI 
770 
1813 
31 
113 
VI 
1676 
1806 
35 
104 
VII 
1575 
1841 
28 
98 
VII 
3044 
1834 
28 
97 
VIII 
1572 
1864 
23 
82 
VIII 
2367 
1853 
19 
82 
4308 
' 7 . ..1 
8533 
Mean period, 32.7 
Mean period, 31.6 
Omitting generation VIII, 34.3 Omitting generation VIII, 33.7 
The first family, denoted by A, is also presented in Diagram 
1, which graphically represents the dates of birth and the lines 
of descent of nearly 1,300 descendants of the ancestor placed at 
the top upon the line of the year 1637, although a few of the 
lines marking descent are omitted in the later generations on 
account of insufficient space. But all the known dates of birth 
in each generation are located upon the heavy lines, the mean 
date of birth for each generation being shown by a light hori¬ 
zontal line. 
In this family the successive inter-generation periods are 
shown to be 40, 35, 29, 33, 36, 34, 26, together amounting to 
233, and giving a mean period of 33.3 years. The exceptional 
brevity of the last period, however, suggests that the eighth 
