Reference for Menachot 194:8

אלא חיק האמה כניסה אמה רוחב כניסה גבולה אל שפתה סביב כניסה

to separate between blood that must be sprinkled above and blood that must be sprinkled below. How then could it have taught in connection with the burnt-offering of a bird that [the priest] went up the ascent, passed on to the sobeb and came to the south-eastern horn, nipped off the head close by its neck and divided it asunder, and drained out the blood on the altar wall, and that if he did it even one cubit's distance below his feet,<span class="x" onmousemove="('comment',' I.e., he bent down low and drained out the blood of the offering against the wall of the sobeb upon which he stood.');">¹¹</span>

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