"According to a table of Euler, calculated on a mortality of 1 in 36, if the births be to the deaths in the proportion of 3 to 1, the period of doubling will be over 12 years and 4-5ths. And this supposition is not only a possible supposition, but has actually occurred for short periods in more countries than one. Sir William Petty (_Polit. Arith._, p. 14.) supposes a doubling, possible in so short a time as _ten_ years." What difficulty, then, can there be (knowing the promise in Gen. xvii. 6.) in believing that the number of the Israelites in Egypt doubled itself every _fourteen_ years? F. A. P.S. Assuming what Malthus considers an ordinary rate of increase, when population is unchecked, viz. a doubling in 25 years, 70 persons in 430 years would increase to 10,539,000: which is what ÆGROTUS wishes to know. At Vol. v., p. 11., ÆGROTUS suggests that the "600,000 men" of Ex. xii. 37. mean "men and women." He will find some valuable "Notes" on Hebrew statistics in the 1st and 2d chapters of Numbers, that appear to militate against his theory! (Numb. i. 1, 2, 3., ii. 32.) A. A. D. SERJEANTS' RINGS AND MOTTOES. (Vol. v., pp. 59. 92. 110.) The following will, I believe, be found to be a _correct_ list of the Serjeants' mottoes during the last twenty years. The Law Reports not being probably accessible to all your readers to whom the subject may be one of interest, I have compiled this list with the view of preserving (in as brief a form as possible) in your pages, what is now scattered through many volumes. Serjeants.