I stayed over at a friend of mine who had a wonderful book which gave the history and etymology behind lots of phrases, words, etc.
Skylark was one we got on to.
It's a nautical phrase from the turn of the 19th century (ah yes, when brittania ruled the waves) which originally meant to 'frolic and play'. The skylarks would be seen around the top of the masts and riggings and the seamen, working hard from below, would see their light-hearted singing and frolicking as the antithesis to their hard and serious labour. 'Larking around' was then derived from this, I never knew the original was 'skylarking'.
My favourite was 'Scratch my back I'll scratch yours'
If one of the crew on the ships ever did something wrong and the captain chose to have him flogged, it was seen as being below the captain or an officers station to carry out the flogging. The seamen who had carried out the transgressions would actually flog each other. The night before, in the brigg below deck where they were locked up until the flogging at dawn, they would make a deal with each other: don't whip me too hard, I won't whip you too hard, 'scratch my back, I'll scratch yours'
Totally off topic, but Dentist did say he felt like he was watching paint dry (incidentally, you don't need a book to explain that phrase I'm sure!)
