No 2739, Sunday 19 May 13

ACROSS
1   Circles rook with pieces following opponent's opening (6) ORBITS {O}{R}{BITS}
4   Catch post in western extremity (5,3) LANDS END {LAND}{S END}
9   25 left by river (5) LOUSE {L}{OUSE}

LOVE IS...

10 What may be taught at school about helium, head of mathematics is to test (9) CHEMISTRY {C{H}E}{M}{IS}{TRY} (Addendum - {C}{HE}{M}{IS}{TRY} - See comments)
11 Letter from Greece about a dance (7) LAMBADA {LAMB{A}DA}
12 Spanish wine imbibed by river results in easing of tension (7) DETENTE {DE{TENT}E}
13 Pretty sweet carton (9-3) CHOCOLATE BOX {CHOCOLATE} {BOX}
17 Dorset lighthouse seen in harbour - come ashore on account (8,4) PORTLAND BILL {PORT}{LAND} {BILL}

20 Le Carré novel, more readable (7) CLEARER* My COD
21 Vessel's gone out with everybody on board (7) GALLEON {G{ALL}EON*}

23 Cabins for the upwardly mobile? (5,4) CABLE CARS [CD]
24 Quiet old character in trim (5) PRUNE {P}{RUNE}
25 Hanger-on ruined pair's tea (8) PARASITE*
26 Want to change sides (6) DEFECT [DD]

DOWN
1   Painting, superficially attractive, depicting ecological problem at sea (3,5) OIL SLICK {OIL} {SLICK}
2   Rodgers and Hart song, sad, second on (4,4) BLUE MOON {BLUE} {MO}{ON}
3   Greek character volunteers after article (5) THETA {THE}{TA}
5   Type of cattle under an age BSE affected? (8,5) ABERDEEN ANGUS*

6   Unfortunately did for two found washed up on a beach? (9) DRIFTWOOD*

7   Carry on with former nurse (6) EXTEND {EX}{TEND}

8   Poet in study, in need of a drink first (6) DRYDEN {DRY}{DEN}
10 Sort to leave acting role (9,4) CHARACTER PART {CHARACTER} {PART}
14 Sold us roe, processed, having no smell (9) ODOURLESS*
15 Cushy job at home in stable (8) SINECURE {S{IN}ECURE}
16 Ringing dope in factory (8) PLANGENT {PLAN{GEN}T}
18 Step one is to climb across cold mass covering the top of Everest? (6) ICECAP {1}{C}{ECAP}<=
19 Don't forget about leaving part (6) MEMBER reMEMBER
22 Circles vowel in error (5) LAPSE {LAPS}{E}

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