Mixing Trough and Mortar Hoe with a Holed Blade

Mortar and plaster are mixed by hand in a long, shallow trough with a mortar hoe: a square-bladed draw hoe, blade at about a right angle to the handle, with large holes through the blade so the mix passes through it. Nail up a plank trough with sloped ends, forge a holed blade with a socket, and fit a long ash handle. The picture: our diagram, the trough and the holed hoe.