arrows walk too (the walking keys go by place, not letter: Z Q S D on a French keyboard)

Shift run · Space jump; in the air, press it again or hold it to glide

wheel camera distance

C the manifold (a small piece of a manifold, drawn with the coordinate grid of a chart): C calls it, C again steps on; then W flies, the mouse steers, Space rises, Shift sinks, and C lands on open ground

Enter reads, as E does; in an exhibit, ← → change its number

G call Lemma, or let it lead you to what it has pointed out

T fly with Lemma to the next stop of a walk

X send Lemma away (G brings it back)

J your journal: the walks and your progress

Y the years: the town builds itself, by the years in the files’ headers

N music and sound · Q quality (low for integrated graphics)

P frame times · H this page