This crossword No. 12666 clues and answers were published on Tue 14 Dec 2010 and the puzzle can be visited by following The Guardian Quick Crossword No. 12666 link.
All Across Clues and Answers:
1-across – Foam-producing substance : BUBBLEBATH
7-across – Especially : ABOVEALL
8-across – Flightless bird from South America : RHEA
9-across – Stopper — advertise : PLUG
10-across – No longer in general use : ARCHAIC
12-across – Hill-climbers, water-fetchers and fallers? : JACKANDJILL
14-across – : SCHERZO
16-across – Human egg : OVUM
19-across – Building bricks for children : LEGO
20-across – In a civilised manner : POLITELY
21-across – Area with ramshackle buildings : SHANTYTOWN
All Down Clues and Answers:
1-down – 1940s’ jazz characterised by virtuosity : BEBOP
2-down – Pass the night in the open air : BIVOUAC
3-down – Page : LEAF
4-down – City on the Danube : BELGRADE
5-down – Set fire to — hand-held light : TORCH
6-down – Mild and pleasant : GENIAL
11-down – Almond paste : MARZIPAN
12-down – Rider in a race : JOCKEY
13-down – Done in a test tube : INVITRO
15-down – Point in time fixed by some great event : EPOCH
17-down – Type of fruit : MELON
18-down – Make weary through being overly sweet : CLOY
This crossword has in total 23 where 11 are across and 12 are down.