I would tend to agree with both of the Yorkshireman's suggestions.  But add
one more.

1a - the man making them was fitting them together in sets, so the wedge
fit the body well.  We see a similar numbering scheme on wooden tool
chests, where the carcass, and all the drawers are, at times, marked with
the same number.

Kirk in Half Moon Bay, CA, slaving away over a hot hard drive all day.  Not
how I imagined it.

On Sat, Jan 9, 2021 at 12:33 AM yorkshireman@y... <
yorkshireman@y...> wrote: