English: “On the wall of the altar” — on the wall of the altar, and not on the wall of the ramp.
In the sugya: The precise phrase “kir ha-mizbe’ach” excludes nearby surfaces that are not the altar wall itself. The ramp (kevesh) has its own wall; the blood must go onto the altar’s wall, not the ramp’s.
Type of Learning
Miyut from “wall of the altar” — not the wall of the ramp.
What Is Learned
Blood is drained onto the altar wall proper, not onto the ramp. The verse’s specification of “kir ha-mizbe’ach” is the source for excluding the kevesh as a valid surface for mitzuy.