QUICK

ACROSS

8 Constituent of bones (7) 9 Assumed name (5) 10 Brushed (the floor) (5) 11 Domestic cockerel (7) 12 Treading quietly and stealthily (2,7) 14 Contents of a balloon (3) 16 Utter (3) 17 Exhibition buildings (9) 19 Traffic jam (5-2) 21 Stoneworker (5) 22 Start (5) 23 Straighten out (7)

DOWN

1 Paper-cutting tool (8) 2 Smoothly and articulately (8) 3 Schism (4) 4 Earliest stage of human development (6) 5 Merry-go-round (8) 6 General idea (4) 7 Old Russian ruler (4) 13 Colonise (8) 14 Non-electric (guitar) (8) 15 Produce a vibrating sound (8) 18 Water in the atmosphere (6) 19 Cease (4) 20 As well (4) 21 Butterfly-like insect (4)