This interesting looking wood joining of a heavy support timber on the porch of the Bollinger mill near Jackson Missouri shows the ingenuity of the builders in the 1800s when they didn’t have modern long bolts, clamps and screws.
Shown here by the image is a locking joint of two timbers used when strength was needed and they didn’t have timbers long enough to reach from one point to another. The joint uses a long wedge end joint which will lock the two pieces together on the bottom and top side of the timber so they can not move closer by sliding together. This makes the timber joint long enough to make the support area long enough to be strong. The joint is then locked in place with a Treenail. A Treenail is a round or rectangular piece of wood that is driven into a hole cut to fit the wooden peg using a heavy maul or hammer. This wood peg keeps the joint from moving apart. All done without any nails, clamps, screws, bolts.