The studies of an actuary depend so much for their success on the accurate and full collection of statistics, that we cannot but feel a deep interest in every effort that is made to improve the method of and to lay down sound principles for obtaining them. Hitherto we have been more especially concerned with the laws of population, vitality, and disease, because they form the basis of the vast extension of life assurance in this and other countries. But in the course of the last few years the progress of social science has brought forward many questions tq. which the doctrine of probability as to the recurrence of events may be applied, which, though not strictly within the limits of our professional pursuits, afford many opportunities for the use and extension of our science.