The method proposed by the late Sir J. W. Lubbock ov approximating to the value ov a life annuity, appears hitherto to hav been very littl notist by mathematicians and not at all by practical men. It was demonstrated by him in the Cambridge Philosophical Transactions for the year 1829, in a paper entitld “On the Comparison of various Tables of Annuities”; and a short account ov it is also givn in the articl Probability, publisht by the Useful Knowledge Society, and very offen bound up with David Jones's work on Annuities: see § 56, p. 36. The former paper was reprinted in the Assurance Magazine (vol. v, p. 277). The original is disfigurd by numerous misprints, which ar all faithfully reproduced in the reprint; and when we add that very littl numerical illustration ov the application ov the method is givn, we hav probably said enuf to account for its attracting so littl attention in any quarter. Considerd as a means ov approximating to the value ov an annuity, the formula has been superseded by the simpler one givn by Mr. Woolhouse; but I believ it may still be practically useful in som cases.