PREFACE

The Handbook for 1956 is the 48th issue and its circulation is 6000. The Officers of the Society appreciated the increase in advertisements which will help to meet our mounting expense.

In this issue the number of pages has been increased by eight, and a number of changes have been made: predictions are given for the dates of maxima of representative variable stars; the material on meteor showers has been completely revised; the table of precession again appears; the table of the brightest stars has been completely revised, giving more information than before. Celestial distances given herein are based on the standard value of 8.80" for the sun’s parallax, not on the more recent value 8.790" determined by Sir Harold Spencer Jones; and the calculations for Algol are based on the epoch 2434576.5110 and period 2.86731 days as published in the 1954 International Supplement, Kracow Observatory.

We are indebted particularly to Dr. Daniel L. Harris of Yerkes Observatory for his compilation of the photometric data for the table of the brightest stars; to Dr. W. W. Morgan, also of Yerkes Observatory, and Prof. R. v. d. R. Wooley of the Australian Commonwealth Observatory, for spectral classifications for the same table. Special thanks are due Mrs. Margaret W. Mayall, A.A.V.S.O. Recorder, for the predictions of times of maxima of the long-period variables. Cordial thanks are tendered to all those who assisted in preparing this volume, especially to the following: Gustav Bakos, Marion Burgess, Charles M. Good, Bernard Jones, John Morrison, Donald Morton, Arlyne Rosenblat, Isobel K. Williamson, G. Marcy Wiseman and Dorothy Yane.

Our deep indebtedness to the British Nautical Almanac and the American Ephemeris is thankfully acknowledged.

C. A. Chant
David Dunlap Observatory,
Richmond Hill, Ont., June 1955.