Midrash su Levitico 4:25

1) (Vayikra 4:25): ("And the Cohein shall take of the blood of the sin-offering with his finger.") "with his finger .. and he shall take" (i.e., "with his finger" applies to "and he shall take") — that he take with his right ([index] finger [this being derived by identity from the instance of a leper]). "with his finger" and he shall place" ("it on the horns of the altar") — that he place with his right (finger, "with his finger" applying also to "and he shall place.") R. Shimon said: Is it written ("And he shall take with his) "hand"? (or "finger" [that we may derive "right" by identity from the instance of a leper? R. Shimon holds that a phrase, (in this instance "with his finger") is expounded proactively (as applying only to "and he shall place," and not retroactively (as applying to "and he shall take.")]. And since "hand" (more specifically, "finger") is not written (in respect to "and he shall take"), if he takes it with his left, it is kasher. "and he shall place it on the horns of the altar of the burnt-offering" — and not on the horns of the inner altar. For (without the exclusion clause) would it not follow (that he should place it on the horns of the inner altar), viz.: The high-priest is distinct from the (lay) individual (in that he brings a bullock), and the nassi (is distinct from) the individual (in that he brings a he-goat). Just as with the high-priest, the blood of his sin-offering enters within (the heichal), so with the sin-offering of the nassi, the blood of his sin-offering should enter within. It is, therefore, written (to negate this): "and he shall place it on the horns of the altar of the burnt-offering" — and not on the horns of the inner altar.

2) And its (remaining) blood he shall pour at the base of the altar of the burnt-offering" — Apply (the law of) "base" (i.e., that the remainder is to be poured at the base) to the altar of the burnt-offering. (i.e., that the remainder of the blood of the burnt-offering is to be poured at the base.) (But perhaps it is meant to teach that the blood of the burnt-offering itself is to be applied [on the horns that are] in alignment with the base [to exclude the southeast corner, where there is no base]!) R. Yishmael said: (The verse is not needed for that, for) if the remainder (of the blood) of the sin-offering, which does not effect atonement is poured at the base, then the "beginning" blood of the burnt-offering (i.e., that applied to the horns) which does effect atonement, how much more so should it be applied at (i.e., in alignment with) the base! R. Akiva said: If the remainder of the sin-offering, which does not effect atonement and is not fit for atonement is poured at the base, then the "beginning" blood of the burnt-offering, which does effect atonement, and which is fit for atonement — how much more so must it be applied at (i.e., in alignment with) the base! What, then, is the intent of "at the base of the altar of the burnt-offering" — that the law of "base" (i.e., pouring the remainder at the base) apply to the altar of the burnt-offering." "at the base of the altar of the burnt-offering" — the southern base.

3) I might think it is the western base, (as it is in the case of inner sin-offerings), but this is to be negated. For just as we find that when he leaves the heichal he pours the (remaining) blood on the first base he chances on, (the western), so, in descending from the altar (after the blood applications of the outer sin-offering), he pours the (remaining) blood on the first base he chances on, (the southern).