The stool declared loudly by snapping every black walnut rung I made- that it must be white oak throughout.  OK, says I, you win.

Still much work to be done, however, as of yet the  most complete sense of a stool that has pretty much dictated itself, and made me sweat in the process, and I still have to build his hopefully less mercurial brother.

Below:  shaping the underside of the seat.