This crossword No. 9302 clues and answers were published on Thu 24 Feb 2000 and the puzzle can be visited by following The Guardian Quick Crossword No. 9302 link.
All Across Clues and Answers:
1-across – Unmarried : SINGLE
4-across – Formality : STARCH
8-across – Subsequently : LATER
9-across – Behave boisterously : ROISTER
10-across – Dirigible : AIRSHIP
11-across – Bracing seaside air : OZONE
12-across – Discharge of electricity in the atmosphere : LIGHTNING
17-across – Deduce : INFER
19-across – See 21 : BALLOON
21-across – Deterrent to low-flying air attacks : BARRAGE
22-across – Sponge : CADGE
23-across – Staggered : REELED
24-across – Although : ALBEIT
All Down Clues and Answers:
1-down – Of trees : SYLVAN
2-down – Unaffected – musical character : NATURAL
3-down – Deciduous coniferous tree : LARCH
5-down – Capital of Libya : TRIPOLI
6-down – Proportion : RATIO
7-down – Skin disease – shingles, for instance : HERPES
9-down – Trustworthy : REPUTABLE
13-down – Rubbish : GARBAGE
14-down – Person from Tyneside : GEORDIE
15-down – Sawn wood : TIMBER
16-down – Coin : INVENT
18-down – Smithy : FORGE
20-down – Regional : LOCAL
This crossword has in total 26 where 13 are across and 13 are down.