This crossword No. 12172 clues and answers were published on Thu 14 May 2009 and the puzzle can be visited by following The Guardian Quick Crossword No. 12172 link.
All Across Clues and Answers:
1-across – Cosmological hypothesis concerning all fundamental particles — retrying tosh : STRINGTHEORY
9-across – Parcel out : ALLOT
10-across – Mound of insects : ANTHILL
11-across – Far Eastern desert : GOBI
12-across – Mexican holiday destination : ACAPULCO
14-across – Hens? : LAYERS
15-across – Stiffener : STARCH
18-across – The USA : UNCLESAM
20-across – Swindle : SCAM
22-across – US letter’s letters and numbers : ZIPCODE
23-across – Love : ADORE
24-across – Well established : LONGSTANDING
All Down Clues and Answers:
2-down – High chest of drawers : TALLBOY
3-down – Taking an active and lively interest : INTO
4-down – Oblique impact : GLANCE
5-down – Places of danger : HOTSPOTS
6-down – Large recess — type of window : ORIEL
7-down – Common bunting : YELLOWHAMMER
8-down – Variety of beet used as cattle feed : MANGELWURZEL
13-down – Highest level of a wood : TREETOPS
16-down – US mammal with a fox-like face : RACCOON
17-down – Snapper’s equipment : CAMERA
19-down – Castrated cock fattened for eating : CAPON
21-down – Shakespeare : BARD
This crossword has in total 24 where 12 are across and 12 are down.