Answers to clues in italics must become 15 (hyphened) to create grid entries. Definitions of these entries are supplied by unclued lights, one of which consists of two words. Elsewhere ignore two accents.
 

Across

 
1    Convince court without question, wearing dark blue (8)
11    Endless praise in resort prepared for sharks (12)
14    Melodies soprano practises (7)
17    Quarrels providing force in manuscript (5)
18    Bullfighter rushed right round (6)
22    Passage about heartless prison camp in speech (8)
23    Horse we trained in whatever place? (7)
24    Struggle to grab a bone (6)
25    Be agitated and refer to article (6)
27    Figurine in brown and silver by artist (7)
29    Traditionalist unhappy with church in charge (8)
33    Disc, Chinese design on shield (6)
34    Sheep following lane around wood (5)
37    Poet nearly broken by strain getting back in groove (7, hyphened)
38    Edmund’s cunning fellow with Lear? Not half (5)
39    A favourite allowance for commission (12)
40    Cattle dead? Appeal for help (4)
41    Measure boundary
 

Down

 
1    Bristle under extremes of pressure to make money (6)
2    River beginning to confuse one on board? (4)
4    When fastening matting, working gropingly (7, two words)
5    Prepared to conserve energy, stopped working
6    Nut runs amok and twists backwards (7)
7    Learner in game tyrant treated scoldingly (11)
8    Trouble after debtor makes bow (5)
9    Trick for all to see concerning parrot
10    Succeeded in destiny, shedding last veil (6, hyphened)
13    Our team among socialists supporting cheers for composites (8)
19    People to grasp method and locate solid solution (10)
20    Scots rather upset for example with rugby’s ending
21    Apparatus for hoisting broken glass here (9)
26    Diagrams of interactions over month filling room up (7)
28    Blunder, no good with plough once scared (7)
29    Part of verse drama declared Miltonic
30    Broken soul rendered tense (6)
31    Old song of lamentation from wraith renewed (6)
32    Research involving middle of 3 devices (5)
36    Opening track (4)
 
A first prize of £30 for the first correct solution opened on 18 April. There are two runners-up prizes of £20. (UK solvers can choose to receive the latest edition of the Chambers dictionary instead of cash— ring the word ‘dictionary’.) Entries to: Crossword 2254, The Spectator, 22 Old Queen Street, London SW1H 9HP. Please allow six weeks for prize delivery.