WILLIAMS' CASE.—3 BLAND. 249

an additional estimate must be made of his expectation of receiv-
ing a profitable appointment, or of his marriage; and then, the
value of the two contingencies taken together may be calculated
in like manner as in the making of an estimate of the combined
value of two or more lives; except, that in the case of two, or
more lives, each life adds somewhat to the value of the expec-
tancy, whereas a contingency annexed to a life diminishes its
value. There may be very great difficulty in determining the
* present value of a life interest subject to such superadded
contingency even where there may be nothing in it that con- 236
travenes any general legal policy or constitutional provision.
Const. Maryl. Art. 54; Heathcotc v. Paignon. 2 Bro. C. C. 170;
Kircudbright v. Kircudbright, 8 Ves. 51. Nevertheless, let the sup-
eradded contingencies be what they may, they do not prevent as-
certaining the value; and therefore, they must be valued, if re-
quired. Kircudbright v. Kircudbright, 8 Ves. 64. For although it
has been said, that an estate for life, depending upon the contin-
gency of marrying and having issue, is, in general, not the subject
of estimate or calculation. Ardglasse v. Muschamp, 1 Vent. 238;
Wiseman v. Beake, 2 Vern, 121; Nichols v. Gould, 2 Ves. 423; Bowes
v. Heaps, 3 Ves. & Ben. 120; Bakers. Bent, 4 Cond. Cha. Rep. 398;
S. C. 5 Cond. Cha. Rep. 432; Portmore v. Taylor, 6 Cond. Cha. Rep.
101, note. Yet so far as any observations have been made upon
the numbers who marry, and who do not marry, it is as easy, from
such observations, to form tables of the expectation oi marriage as
of life; and both may thus be alike made the subject of estimate
and calculation. 1 Price Obser. 45, 86, 88: 2 Price Obsev. 105, 118.
It is by no means uncommon to grant annuities and estates for
life during widowhood, until marriage, or depending on marriage,
and having issue; Henley v. Axe, 2 Bro. C. C. 17; Davis v. Marl-
borough, 2 Swan. 149, note; yet few observations have been made on
the probabilities of marriage.

About the year 1825, Dr. Grenville, a physician and accoucheur
of very extensive practice connected with the Westminster Dispen-
sary, and severs other public institutions in or near London, on
being called as a witness before a committee of the House of
Commons, stated, that his attention had been frequently directed
to the statistical questions of the increase of population among the
poor; and that therefore, availing himself of his various means of
information, he had made an analytical register in which he had
entered the information he had obtained from mothers. He had ex-
bited a register of the cases of eight hundred and seventy-six
women, all of the lower classes, showing how many of that num-
ber had married in each year, from thirteen to thirty-nine years of
age. Considering the state of society in England, the remark
would seem to be just, that among an equal number from the
middling, or the higher classes, we should not probably find so