[Margaret Pilkington]

I think that Pop goes the weasel referred to pawning stuff.......didn't they used to say they were taking Dad's best suit to the 'pop shop'.......the half a pound of tuppeny rice and the treacle were goods that would be bought as a result of getting cash on articles pawned.
Ring-a ring a roses certainly referred to the black death. Apparently the rash would come in a circle and was pink. Hence the reference to roses...the atishoo was the cold like symptoms...and of course 'all fall down' refers to the numbers who dies as a result of catching the plague.