Exodus 29:12

29:12 and take some of the blood of the bull and put it on the horns of the altar with your finger; all the rest of the blood you are to pour out at the base of the altar.

Exodus 29:36-37

29:36 Every day you are to prepare a bull for a purification offering for atonement. You are to purge the altar by making atonement for it, and you are to anoint it to set it apart as holy. 29:37 For seven days you are to make atonement for the altar and set it apart as holy. Then the altar will be most holy. Anything that touches the altar will be holy.