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It isn't a fable, mercuries neighbor makes life able, But I am next to him on a different table.

A tool of math with a royal name Of wood, steel or plastic frame Tiny ticks count up or down Governs space, it earns a crown

The more you take, the more you leave behind. What am I?

I walk on four legs in the morning, Two legs in the afternoon, And three legs at night, What am I?