Tenon

A rail had worked loose on the old garden bench by the south wall, and Nyra meant to mend it before the frosts set the wood hard. She brought the girl to the bench and showed her the end of the rail, a squared tongue of oak cut to slot into a hollow in the upright. The girl had thought the rail was only pushed against the post, and she was surprised to see the shaped tongue slide free when Nyra drew it out.

This squared end is the tenon, Nyra told her, and it is cut to sit inside a pocket in the post that the makers call the mortise. The tenon does the joining, she went on, for it carries the weight of the rail down into the heart of the post rather than onto the surface alone. A joint made so can bear a great deal and never shift, so long as the tenon is cut true and seated full.

The girl wished to keep the measure of it, and Nyra let her set the length of the tenon in the margin and the depth of the pocket it went into. A book gathers what can be set down in a line and counted, and leaves the rest to the one who was there. The figure of the cut can travel to the next maker, she said, but the feel of a tenon drawing snug into the mortise is a thing the hands learn and the page could not carry.

They pared the shoulders of the tenon with a chisel until the fit grew close, and Nyra had the girl push the rail home while she held the post steady. The tongue of oak went into the pocket with a small firm sound, and the bench stood square again under their hands. The girl pressed on the rail and felt no give at all, and she marvelled that so plain a tongue of wood could hold a whole seat together.

Nyra wiped the chisel and noted the mending in the garden book, the date beside it in faint lead. Then she set the bench back against the warm stone of the wall, where it would season through the winter. The book keeps the measure of the tenon, and you keep the seating of it.