On my first morning in Canada I rose early and before anybody else was about.

And as I surveyed my new surroundings the first thing my eye lit on was this chair.

I could not believe it. - Here I was, five or more thousand miles from home on a different continent, and the first thing I see is another variation of the 'Sussex' chair!

All the fundamental distinguishing features are there: the back as a continuation of the leg; the arm-rest dowelled into the back; the upright support member dowelled into the underside of the arm-rest and screwed into the side of the seat rail.

But what is so interesting, to me at least, is the solution devised to counter the constant lateral pressure exerted by seated occupants.

In this chair, the arm support member extends beneath the seat rail just enough to allow for a member to be introduced between the two upright arm supports. This clearly, and ingeniously, transfers much of the lateral pressure from one arm to the other, thus imposing a corrective force on the opposing arm.
But the flaw to this solution is that it imposes an even greater reliance on the (mechanical) screw fixing, which, as I have previously mentioned, is inherently weak.

The one-member leg and back. Somewhat too straight, in my view, with the curve too high to aid comfort.

The upright support member dowelled into the underside of the arm-rest and screwed into the side of the seat rail.

The member connecting the arm-rest supports just beneath the seat.

The provenance of this chair is uncertain.

To my eye it has a distinctly North American look, but it is possible that it was made in England and brought to Canada by my sister-in-law's grandfather in 1924.
She has been aware of it all her life and it was known as 'Grandpa's chair'.