A PERSONAL HISTORY OF H.M. NAUTICAL ALMANAC OFFICE 30 October 1930 - 18 February 1972 By Donald H. Sadler Edited by George A. Wilkins SIDFORD, DEVON, 2008 2 DONALD H. SADLER © Copyright United Kingdom Hydrographic Office, 2008 A Personal History of H. M. Nautical Almanac Office by Dr. Donald H. Sadler, Superintendent of HMNAO 1936-1970, is a personal memoir; it does not represent the views of, and is not endorsed by, HMNAO or the United Kingdom Hydrographic Office. The United Kingdom Hydrographic Office grants permission to reproduce the document, in whole or in part, provided that it is reproduced unchanged and with the copyright notice intact. The photograph of Sadler taken when President, is reproduced by kind permission of the Royal Astronomical Society (RAS). If you wish to reproduce this picture, please contact the Librarian, Royal Astronomical Society, Burlington House, Piccadilly, London, W1J 0BQ, United Kingdom. This work may be downloaded from HMNAO’s website at http://www.hmnao.com/history PERSONAL HISTORY OF H.M. NAUTICAL ALMANAC OFFICE, 1930-1972 3 SUMMARY OF CONTENTS Preface 10 Forewords by Donald H. Sadler 13 Prologue 15 Part 1: At Greenwich: 1930–1936 17 1. First impressions 17 2. Mainly about the work of the Office 22 3. Mainly about L. J. Comrie and his work 30 Part 2: At Greenwich: 1936–1939 39 4. Change and expansion 39 5. New developments 46 6. Procedures and moves 53 Part 3: At Bath: 1939–1949 57 7. Early days at Bath (before the move to Ensleigh) 57 8. From the move to Ensleigh to the end of the war 67 9. The Admiralty Computing Service 75 10. The post-war period (to about the end of 1947) 80 11. Major changes in the post-war period 88 Part 4: At Herstmonceux: 1949–1972 99 12. Early years at Herstmonceux: 1949–1951 99 13. End of the Spencer Jones era: 1952–1955 109 14. Woolley becomes Astronomer Royal 119 15. Period as General Secretary of the I.A.U. 132 16. Transfer to the Science Research Council 141 17. A change of duties 155 Epilogue 160 Appendices 161 4 DONALD H. SADLER CONTENTS PREFACE 10 FOREWORDS BY D. H. SADLER TO HIS MANUSCRIPTS 13 PROLOGUE — PERSONAL HISTORY TO 1930 15 At Trinity College, Cambridge 15 Looking for a job 16 PART 1: AT GREENWICH: 1930–1936 17 1 First impressions 17 Appointment in H. M. Nautical Almanac Office 17 Staff and accommodation in 1930 17 Early work in the N.A.O. 18 The Daniels and Richards 19 Emden's equation and other tasks 20 Work of the junior staff 21 2 Mainly about the work of the Office 22 The method of cyclic packs 22 The use of punched-card machines 22 More on the use of cyclic packs 24 The use of Brown’s Tables 24 Status of N.A.O. work in 1935 25 Various incidents involving Comrie 25 The occultation programme 26 Eclipse and comet work 27 Navigational work 27 Use of National machines 28 3 Mainly about L. J. Comrie and his work 30 Comrie and mathematical tables 30 Comrie and calculating machines 31 Comrie’s approach to computing 31 Comrie as a ‘consultant’ 31 More on Comrie and mathematical tables 32 Comrie and the International Astronomical Union, etc. 32 Comrie’s personal relations 33 Comrie and bureaucracy 34 Comrie’s marriages 34 Comrie’s relations with N.A.O. staff 35 Comrie and the N.A.O. complement 35 A note on my establishment and appointment 36 PERSONAL HISTORY OF H.M. NAUTICAL ALMANAC OFFICE, 1930-1972 5 Other appointments 36 ‘Winds’ — a job for the War Office 37 Comrie's final bid for more staff 37 PART 2 AT GREENWICH: 1936–1939 39 4 Change and expansion 39 Changes in administrative responsibility for the N.A.O. 39 The work and staffing of the Office 41 The post of N.A.O. secretary 42 Initial recruitment of junior staff 43 Expansion for air navigation 44 Acquisition of new calculating machines 45 5 New developments 46 The Occultation Supplement 46 Air Almanac and Astronomical Navigation Tables 46 Introduction of the Air Almanac 47 Astronomical Navigation Tables for use in the air 48 I.A.U. General Assembly in Stockholm (1938) 49 A threatened dispute on copyright 50 Apparent Places of Fundamental Stars 51 Other publications 51 6 Procedures and moves 53 A comment on official procedures 53 Move to Devonport House 53 Evacuation to Bath 54 Appointment as Secretary of the Royal Astronomical Society 55 PART 3: AT BATH 1939–1949 57 7 Early days at Bath (before move to Ensleigh) 57 Early days in Bath 57 My billets in Bath 58 Initial work in Bath 59 Mathematical tables 60 Wartime astronomical projects 60 Black-out times and repayment work 61 Ryde night-illumination diagrams 61 The astrograph 61 Coriolis effect 62 Twilight for air navigation 63 Non-astronomical work of the Office 63 6 DONALD H. SADLER Bomb Ballistic Tables 63 A job for Massey 64 Security at Laggan and war service 65 Life in war-time 66 A storm at Bath 66 Bombing of Hammond’s printing works 66 8 From the move to Ensleigh until the end of the war 67 The move to Ensleigh 67 The bombing of Bath in 1942 67 Staff changes 68 Duties of the staff 69 Calculating and punched-card machines 70 Specialist course for air navigation 71 Relations with the Royal Air Force 72 Computations for the DECCA Navigation system 73 A personal note 74 9 The Admiralty Computing Service 75 Preamble 75 The beginning of the Admiralty Computing Service 75 The first job — on the Taylor bubble 76 Recruitment of staff 77 Range and background of A.C.S. jobs 78 10 The post-war period (to about the end of 1947) 80 A visit to Germany 80 The post-war period in Bath 81 Post-war changes in staff 82 Formation of the Mathematics Division at N.P.L. 83 Captain Schmidt and Decca for Denmark 84 Cooperation with the Spanish Almanac Office 84 The Star Almanac 85 The Institute of Navigation 85 Honours 86 Other events of the post-war period 86 11 Major changes in the post-war period 88 Visit to the U.S.A. in 1947 88 Revision of the Abridged Nautical Almanac 89 Tables for marine navigation 90 Further comments on tables for navigation at sea 91 New equipment and other topics of discussion 92 The return journey from the U.S.A. 92 PERSONAL HISTORY OF H.M. NAUTICAL ALMANAC OFFICE, 1930-1972 7 The General Assembly of the I.A.U. in Zurich in 1948 92 Concern as to the future site of the Office 94 The new Scientific Civil Service 95 A search for a ‘celestial mechanic’ 96 Other staff changes 97 Planetary Co-ordinates 97 The move to Herstmonceux 97 PART 4 AT HERSTMONCEUX 1949–1972 99 12 Early years at Herstmonceux: 1949–1951 99 Move from Bath to Herstmonceux 99 Early days at Herstmonceux 99 Administrative arrangements 100 The start of the R.G.O. Club 101 Work of the Office 102 Visit to U.S.A. in 1949 102 Conference on Astronomical Constants in 1950 104 Follow-up and other activities 105 Vacation students 105 Visit to North America in 1951 106 Office appointments and activities in 1950 and 1951 107 The Star Almanac for Land Surveyors 108 13 End of the Spencer Jones era: 1952–1955 109 Installation of punched-card equipment 109 Responsibilities of Miss McBain 109 The lunar occultation programme 110 I.A.U. General Assembly in Rome in 1952 110 Navigational work in 1952–1955 111 Institute of Navigation 112 Visits by navigators 113 A minor annoyance 113 Responsibilities of Dr Porter 113 Visit by Professor Herrick 114 Activities in 1952–1955 continued 114 Loss of position in computing 115 Visit to the U.S.S.R. in 1954 115 Conformity of the almanacs 116 Marriage to Miss F. M. McBain 117 I.A.U. General Assembly in Dublin in 1955 117 The change of Astronomer Royal 118 8 DONALD H. SADLER 14 Woolley becomes Astronomer Royal 119 Woolley becomes Astronomer Royal 119 Woolley’s administrative style 119 Anecdotes about Woolley 121 Role of the Astronomer Royal 121 Work of the N.A.O. in 1956–1959 122 Visit to Washington and Montreal in 1956 123 Committee on the definition of the second 123 Preparation of Interpolation and Allied Tables 123 Preparation of Subtabulation 124 Visit by Wilkins to U.S.A. in 1957–1958 124 Prediction service for artificial satellites 125 N.A.O. accommodation in the West Building 126 Staffing matters 126 The I.A.U. General Assembly in Moscow in 1958 127 The acquisition of the ICT 1201 computer 127 Staff changes 128 The Explanatory Supplement 128 Other activities in 1958–1959 130 Promotion to D.C.S.O. 130 15 Period as General Secretary of the I.A.U. 132 Relationships of the N.A.O. and R.O. Cape to R.G.O. 132 Appointment as the A.G.S. of the I.A.U. 133 Appointment as General Secretary of the I.A.U. 133 Overseas visits in 1960–1963 135 The I.A.U. General Assembly in Hamburg in 1964 137 Federation of Astronomical and Geophysical Services 137 N.A.O. activities in 1960–1964 137 Retirement of Dr. Porter 138 N.A.O. Reunion in 1963 138 Replacement of the ICT 1201 computer 138 Transfer of R.G.O. from the M.o.D.