8 On the conception cycle, Carville Earle’s research on All Hallow’s Parish yields the following pattern for the period from 1700 to 1776:

Month of

Month of

Percent of Annual

Monthly Index

Conception

Baptism

Births

(Monthly Mean = 100)

Dec-Jan.

Oct.

9.6%

115

Jan.-Feb.

Nov.

4.9%

59

Feb.-March

Dec.

4.3%

52

March-April

Jan.

3.3%

40

April—May

Feb.

8.6%

103

May—June

March

10.0%

120

June-July

April

11.0%

132

July-Aug.

May

8.6%

103

Aug.-Sept.

June

10.2%

122

Sept.-Oct.

July

8.1%

97

Oct.-Nov.

Aug.

11.8%

142

Nov.—Dec.

Sept.

9.6%

115

Computed from data in Earle, in The Evolution of a Tidewater Settlement System, 159; similar but not identical cycles are reported in Rutman, Wetherell and Rutman, “Rhythms of Life,” 30-31; and Kulikoff, Tobacco and Slaves, 256. These data refer to the white population only; as will be discussed in volume 3, the rhythm of seasonality among blacks was different.

9 William Byrd to John Custis, 29 July 1723, Tinling, ed., Correspondence of Three William Byrds, I, 346.