4d) Look up 'gas' instead of 'oxygen' and stare in admiration. (6) G???L?
18d) Secure dram, say, in city of Manitoba (8) no letters
20d) Skittle alley in gym creates small drama (7)
25a) German smuggled drug to artist in 'Aida', say (5,5) ????? O???A
29a) No seats here for substitute stableboy? (8,4) no letters
All help much appreciated