IN a letter in NATURE (Jan. 20, 1921; vol. 106, p. 661) I took occasion to point out that the year of Ramanujan's birth was given in some notices as 1887 and in others as 1888. I wrote at the time to… Expand

Abstract The inequality is which is established by an elementary argument and is shown to lead directly to the evaluation of the integral and to the expression of sin x as an infinite product.

THE principle of crystal analysis by means of vector maps may be indicated briefly as follows. If the electron density throughout a crystal is expressed by a triple Fourier series ρ whose typical… Expand

THE vector map of a projection of the cyclol structure C2 prepared by D. P. Riley and I. Fankuchen1 provides elaborate illustrations of the rudiments of map theory. Particularly is it to be noticed… Expand

628. Note on 617 [V. 1. a. /i.] Vector Proof that the Mid-points P, Q, R of the Diagonals AC, BD, EF of a Complete Quadrilateral are collinear. (In the figure A BCD was a convex quadrilateral; AB met… Expand