Edited by C.A. Chant.

Twenty-Third Year of Publication.

PREFACE

In the present issue of the Handbook there is a much fuller list of stars occulted by the moon than any given heretofore. These have been computed for Ottawa and Toronto, and it is very desirable that they be used by a considerable number of observers in central Ontario and Quebec. Calculations will be supplied for the western parts of Canada if observers can be found to use them.

It may be stated that four circular star-maps, 9 inches in diameter, roughly for the four seasons, may be obtained from the Director of University Extension, University of Toronto, for one cent each; also a set of 12 circular maps, 5 inches in diameter, with brief explanation, is supplied by Popular Astronomy, Northfield, Minn., for 15 cents. Besides these may be mentioned Young’s Uranography, containing four maps with R.A and Decl. circles and excellent descriptions of the constellations, price 72 cents; Norton’s Star Atlas and Telescopic Handbook (10s. 6d.); Olcott’s A Field-book of the Stars ($1.50); McKready’s A Beginner's Star Book ($5.00).

In the preparation of this Handbook the Editor has been assisted by Miss M. S. Burland, Mr. R. M. Motherwell and Dr. R. J. McDiarmid, of the Dominion Observatory, Ottawa; Mr. J. H. Horning and Mr. W. S. Armstrong, of Toronto; and his colleague, Dr. R. K. Young, of the University of Toronto. The minima of Algol have been computed from an observation by Stebbins (Ap. J., vol. 53, 1921), J.D. 2422619.7866 with the period 2.86731077, given by Hellerick (A.N., vol. 209, p. 227, 1919).

Toronto, December, 1930.       The Editor.