This crossword No. 9253 clues and answers were published on Wed 29 Dec 1999 and the puzzle can be visited by following The Guardian Quick Crossword No. 9253 link.
All Across Clues and Answers:
1-across – Run away : DECAMP
4-across – Dissertation – idea : THESIS
9-across – Tool, often adjustable : SPANNER
10-across – Fossil resin : AMBER
11-across – Jolly good : SUPER
12-across – Detachable security device : PADLOCK
13-across – Marine predator : KILLERWHALE
18-across – Bill ? story : ACCOUNT
20-across – Illumination – not serious! : LIGHT
22-across – Offspring : CHILD
23-across – : RIBCAGE
24-across – Rapid : SPEEDY
25-across – Impassive : STOLID
All Down Clues and Answers:
1-down – Neglect : DISUSE
2-down – Fastening – firm grip : CLASP
3-down – Substance that is : MINERAL
5-down – Traditional children shouldn’t be : HEARD
6-down – The lower earth, so to speak : SUBSOIL
7-down – Industrial action : STRIKE
8-down – Antecedent – type of school : PREPARATORY
14-down – Slope : INCLINE
15-down – Flatfish : HALIBUT
16-down – Small dominant inner group : CAUCUS
17-down – Be present at : ATTEND
19-down – Cancelled – destroyed : UNDID
21-down – Holy object of quest : GRAIL
This crossword has in total 26 where 13 are across and 13 are down.