It is sometimes necessary in disentail proceedings to estimate the probability that a husband, who has been married for several years without having any children, will hereafter have issue, either by his present or by a future wife. The probability of issue by a future wife is a subject comparatively well understood, and it is a recognized part of the business of some insurance companies to grant insurances against the contingency of such issue being left surviving at the death of a married man who has no child. The probability of issue by the present wife has been very little considered, and it is this probability that I propose now to discuss. There are very few statistics that will help us in the matter; in fact, I am only aware of two works in which any such statistics are given. Dr. J. Matthews Duncan gives the following table, in his work Fecundity, Fertility, and Sterility (p. 132, 2nd Ed.) :—

Mr. Charles Ansell, Jun., in his Statistics of Families in the Upper and Professional Classes (page 87) gives a table from which columns (1) to (4) of the table on the opposite page are extracted.