Till the age of three years the life of an infant is highly precarious. In the course of the ensuing two or three years, however, it becomes more certain; and at the age of six or seven a child has a greater probability of living than at any other age. By consulting Simpson's tables of the degrees of mortality, at different ages, as applicable to London, it appears, that, of a certain number of children, born at one time, above a fourth of them died in the first year, above a third in two years, and, at least, one half in the first three years. If this calculation is just a wager might be proposed, that an infant, when born, would not live three years. A man who dies at the age of twenty-five is to be lamented for the short duration of his life; and yet, according to these tables, one half of mankind die before the age of three years, consequently, every individual who has passed his third year, far from repining at his fate, ought to consider himself as treated with superior favour by his Creator. But this mortality in children is by no means so great in every place as in London. M. Dupré de St. Maur has proved, by a number of experiments made in France, that one half of the children born at the same time are not extinct in less than seven or eight years. By these experiments it is also shewn, that at the age of five, six, or seven years, the life of a child is more certain than at any other age, and that an equal bet may be laid for 42 years more, whereas in proportion as a child lives beyond five, six, or seven years, the probable number of years it will live decreases. At twelve years, for instance, the equal chance is only for 39 years; at 20, for 33-1/2; at 30, for 20; and thus forward, till the age of 85, when there is an equal chance of living three years longer.[A] [A] In the course of this volume we shall present our readers with a table, at large, of the different probabilities of human life.