Related Clues:

• Thin layer on surface, often wood
• 'Discretion is the . . . . . . part of valour'
• Thin layer glued to a surface
• Thin layer of a fine material on the surface
• Thin on top, but never at the end
• Could it ever get twisted around the north-east and be only skin deep?
• Only on the surface, never on the end
• All on the outside, never at the end of it
• How one might be gambling on improvement
• One does not drink when there's beer about and one is at the races, perhaps
• Does it do more good to get the teetotaller in the ale?
• It's an improvement for the non-drinker to have some drink around
• It's always on the top, never on the bottom
• Only on th surface, never on the end
• It's never at the end, it's always on top