To make angle zinc to be used for constructing an aquarium, after cutting the sheet zinc to the required width, mark it deeply with the scriber or cutter along the bending line on the underside. Then place the zinc along the flat side of a beck-iron or the edge of a hatchet-stake, and, keeping the bending line upon the tool edge, press long edges downwards, commencing at one end and working along the zinc until the opposite end is reached; then smooth down to the angle required with a mallet or dresser.