This crossword No. 9151 clues and answers were published on Tue 31 Aug 1999 and the puzzle can be visited by following The Guardian Quick Crossword No. 9151 link.
All Across Clues and Answers:
1-across – March to October : BRITISHSUMMER
8-across – It jerks reactively : KNEE
9-across – Bully-beef etc : MEATLOAF
10-across – Strong circumstantial evidence : SMOKINGGUN
12-across – Smoked fish : KIPPER
14-across – The cradle of civilisation : GREECE
15-across – It occurs at new and full moon : SPRINGTIDE
19-across – Fee to secure services : RETAINER
20-across – See 1 and 21 : TIME
21-across – It is measured at the 00 meridian : GREENWICHMEAN
All Down Clues and Answers:
2-down – Home electricity supply system : RINGMAIN
3-down – Twist and pull : TWEAK
4-down – Remains : SEMINAR
5-down – Vulgar parlance : SLANG
6-down – Mixture : MELANGE
7-down – Verve : ELAN
11-down – The world of learning : ACADEMIA
13-down – Piece of text or music : PASSAGE
14-down – Non-proprietary : GENERIC
16-down – Restore – recommence : RENEW
17-down – Object of veneration : TOTEM
18-down – Put up with – beast! : BEAR
This crossword has in total 22 where 10 are across and 12 are down.