This is a new subject, and it is with some diffidence that I bring it before the Institute for discussion. We are treading in unfamiliar ways and the pitfalls are many. Aviation hazard is, however, a problem that is daily assuming more and more importance in our business, and it is one that we shall have to face.

(1) The purpose of this paper is to describe the results of further investigations into the possibilities of trigonometrical representation of actuarial functions. The authors’ previous paper (J.I.A. Vol. LIX, p. 256) was concerned mainly with the use of Fourier’s Series, and the simplicity of that series in practice invites its use in any work of this nature. To a large extent Fourier’s Series, or a modification thereof, is employed in the present work, but the authors do not insist that the final formulae suitable for use in practice should be Fourier’s Series.

p. 32, line 7, for 244 read 344

p. 32, line 28, after the word “interest” insert “. Also ax”