Comment by theodoregray

(a) screwdriver bits come above screwdrivers for one simple reason: the mouth bit holder is hilarious and I wanted to put it at the top of the column. (b) column 2 is things you can hit with a hammer: that's why it has stamps, rivets, and nails. It follows hammers because alkali earth metals are somewhat chemically related to alkali metals (e.g. reactive with water to evolve hydrogen, which makes both columns fun to play with). Nail pullers are at the bottom of hammers instead of the bottom of column 2 because the counts worked better that way.