eye. And this rewle is so general in umbra recta, fro the poynt of
oon to 12. And yif thy rewle falle upon 5, than is 5 12-partyes
of the heyght the space be-tween thee and the toure; with adding
of thyn owne heyght.
[42.] Umbra Versa.
Another maner of werkinge, by vmbra versa. Yif so be that
thou may nat come to the bas of the tour, I see him thorw the
nombre of 1; I sette ther a prikke at my fote; than go I neer to
the tour, and I see him thorw at the poynt of 2, and there I sette
5