Crossword solution

The eight unclued lights are the names of flightless birds, past and present. First prize John Honey, Brockworth, Gloucester Runners-up Fran Morrison, Putney, London SW15; David Dickson, Tarrant Monkton, Dorset

Unclued lights were world CHESS champions. Current champion DING was to be highlighted. First prize Gail Petrie, Brean, Somerset Runners-up Hugh Aplin, London SW19; Philip Grindrod, London W4

Each of the unclued lights (with the pair at 15/26) includes D C C (= 700). First prize Rosamund Campbell, Woodstock, Oxon Runners-up J. Smithies, Vale, Guernsey; William Devison, Shaldon, Devon

The literary scholar F.S. Boas used the term Problem Plays (9D) to refer to a group of Shakespearean plays which seem to contain both comic and tragic elements: Measure for Measure (12/36), All’s Well That Ends Well (39/1) and Troilus and Cressida (21/22). First prize J. Bielawski, Southport Runners-up Alastair Aberdare, London SW13; Jeffrey Frankland,

Reading the title as ‘backup’, unclued answers VOLTE-FACE, RETREAT, SPIN, TURN, COUNTER, BACKTRACK, WITHDRAWAL, ROTATE, RETIREMENT and RECOIL had to be entered in reverse. First prize Wyn Lewis, CarmarthenRunners-up Rhiannon Hales, Ilfracombe, Devon; J.E. Green, St Albans, Herts

The unclued lights are some of the brightest Northern Hemisphere stars. First prize Peter Taylor-Mansfield, Worcester Runners-up Jo Anson, Birmingham; Caroline Arms, Ithaca, NY, USA

The unclued lights can all be followed by STREET. First prize Ken Rae, Nordstrand, Wadbister, Shetland Runners-up Colin Boyce, Heathfield, East Sussex; Margaret Lusk, Fulwood, Lancs

The unclued lights are card games, as is the puzzle’s title, SNAP. The pair is 15A/29. First prize Mark Rowntree, Greenwich, London SE10 Runners-up Frances Whitehead, Harrogate, N. Yorks; Alan Pink, Crowhurst, E. Sussex

2603 has the prime factors 19 x 137 which further decompose into (102 – 92) x (42 + 112). Therefore the rubric states: ‘puzzle NUMBER is BRACKET TEN SQUARED MINUS NINE SQUARED BRACKET TIMES BRACKET FOUR SQUARED PLUS ELEVEN SQUARED BRACKET’. First prize John Bennett, Havant, HantsRunners-up Julie Sanders, Bishops Waltham, Southampton; Richard Andrews, Ashford, Middlesex

1D / 25D is a quote by 1A. Remaining unclued lights were all anagrams of gemstones: 15A sapphire; 16A ruby; 13D tiger’s eye; 14D garnet; 15D lapis; 23D moonstone. First prize Ann Moore, Lowestoft, Suffolk Runners-up Margaret Almond, Southampton; Neville Twickel, Tidmington, Warwickshire

The unclued are classical composers. First prize Mike Carter, Kirkby Overblow, Harrogate Runners-up Glyn Watkins, Portishead, Bristol; Lewis Osborne, Newton Mearns, Glasgow

The unclued LIGHTS are horse-drawn carriages. First prize Katherine Gwynne, Topsham, Devon Runners-up Ben Stephenson, Ruswarp, N. Yorks;   William Hare, London SE4

The proverb reads ‘A lie will go round the world while truth is pulling its boots on’ (19/7/29/1D/8/10) by C.H. Spurgeon. The unclued lights at 13, 38 and 39 are BOOTS. First prize Janet Burke, Peterborough Runners-up Geoff Lee, London N1, Alan Connor, Kew, Twickenham

The unclued lights are the former and current names of various products: 2/8A, 12/36, 16/32, 17/34, 13/22. First prize David Caldecott, Bowerchalke, Salisbury Runners-up Elizabeth Feinberg, Rancho Mirage, CA, USAPearl Williamson, Dungannon, Northern Ireland

The couple were VICTORIA (23, 36, 37, 45) and ALBERT (2, 9, 17, 20, 46). 7 was the link. First prize Kenneth Allen, Riddlesden, W. YorksRunners-up P. and A. Hoverstadt, Lymm, Cheshire; Christopher Bellew, London W6

RUNNERS (10), ANSWER (28) and MEADOW (29D) defined FIELD; PROVISIONS (18), MANAGE (38) and PASSENGER (30) defined FARE; and THRUSH (11), PICNIC (16) and COMPILER (20) defined FIELDFARE (above the grid) First prize Steve Reszetniak, Margate, Kent Runners-up Alan Norman, Impington, Cambridge; Amanda Spielman, London SW4

The unclued lights each contained a letter which appeared three times. First prize Janet Hill, Eastbourne, East Sussex Runners-up Gareth Davies, Langstone, Newport, Gwent; Andrew Bell, Shrewsbury, Shropshire

The second half of Résumé (ODQ, 8th edition), by Dorothy (‘Dotty’) Parker (‘Nosey’), reads: ‘Guns aren’t lawful; Nooses give; Gas smells awful; You might as well live.’ First prize Peter Berridge, Spalding, Lincolnshire Runners-up Liz Knights, Walton Highway, Cambs; Peter King, Oxford

1A, 7A, 18A, 40A, 46A and 47A are all on the new Elizabeth Line, which appears in the grid when 25A, 26A and 27A are entered correctly. First prize  Nick Huntley, DarlingtonRunners-up  John Fahy, Thaxted, Essex; Heather Weeks, London SW1