Leviticus 1:3

If his offering be a burnt sacrifice of the herd, let him offer a male without blemish, a strong, healthy animal, with all its limbs and members intact; he shall offer it of his own voluntary will at the door of the Tabernacle of the Congregation before the Lord. The formal dedication of the sacrifice to the Lord took place at the great entrance of the court, or perhaps inside the court itself, where the altar of burnt offering stood. At a later period such a perfect system of offering sacrifices was put into operation that both the slaughtering of the animals and their dissecting was performed with the greatest possible speed, a row of pillars holding heavy beams with hooks being used to suspend the animals after their blood had been caught by the officiating priests.