Wooden conical plug in base of knot?

[Screwtape]

I started my first brush restoration tonight. An old Simms with a knot that was scanty with a bald centre. When I peered down into the centre of the knot, which I would guess at 24 or 25 mm diameter, I saw the tip of a cone in the middle that was maybe 10mm in diameter -- about half the width of the knot.

I thought it was an old glue bump that had lost its covering bristles. However after prying and drilling it with my pocketknife tip until I worked it loose, i found it was a small cone of wood instead.

Unfortunately by then it was totally destroyed and I hadn't thought to take pics before I began because I didn't think the brush was at all unusual.

It looked to me like the brush was made with this little cone inset inside the base of the knot to force the bristles to try to spread out deep inside the handle, which would then constrict them again.

A method to increase the knot's backbone? Or did it maybe let Simms get away with using fewer bristles per knot (which would make little difference to one brush but on several thousand would equal quite a few badgers or boar [in this case I think])?

Have any of you seen something like this before? All the how-to threads in only mention old epoxy in the knots...

 

[Cumberland Sausage]

I haven't seen anything quite like that, but many of the brushes I've restored have had different types of knot construction. On one, the bristles were set in sort of a metal bowl, on another they were secured by numerous strands of what looked like copper wire, on the next there was just a lump of glue.