The outer altar, built of stones untouched by iron, joined with plaster and whitewashed with lime twice a year. Its base, the yessod, is 32 amot on each side and five tefachim high; a setback of five tefachim gives 30 amot and two tefachim up to the sovev, the walkable ledge, thirty tefachim higher; a second setback gives 28 amot and four tefachim up to the surface of the fire. Four hollow horns, one ama by one ama, occupy the corners. It is not centered on the axis of the Heikhal: it is offset nine amot to the south.
Dimensions
- yessod: 32 × 32 amot, 5 tefachim high
- 30 amot and 2 tefachim per side up to the sovev, 35 tefachim above the floor (5 of yessod + 30)
- 28 amot and 4 tefachim per side up to the surface (ma'arakha), 18 tefachim higher
- keranot: four hollow horns, one ama by one ama, at the corners, 5 tefachim high (Rambam, Beit HaBe'hira 2:8)
- 1 ama of walkway (makom hilukh haregel), then a fire zone of 24 amot and 4 tefachim per side
- total height 58 tefachim (≈ 4.64 m), of which 9 amot less one tefach up to the ma'arakha (Rambam, Beit HaBe'hira 2:6, 2:9)
- 32 amot in both the east-west and north-south division of the Azara
- north edge at 60.5 amot from the north wall: center 9 amot south of the axis of the Heikhal
Sources
Project decisionAdopted: the altar shifted to the south, its center nine amot south of the axis of the Heikhal. This is what the measurements of Middot 5:2 give as the Rambam reads them, and the view of R. Eliezer ben Yaakov, who wants the “north” — where the most holy offerings are slaughtered — free of everything, even of the altar (Zevachim 59a). Set aside: R. Yehuda's altar centered in front of the Heikhal (Zevachim 58b), which many models follow, and R. Yosei HaGelili's altar lying entirely in the north (Zevachim 59a). The round figures are those of the first opinion in Middot 3:1, where R. Yosei describes an original altar of 28 × 28 that the returning exiles enlarged by four amot to the south and west. The tour counts as the Rambam does (Beit HaBe'hira 2:7–8), for whom the yessod, the sovev and the horns are measured with an ama of five tefachim (Menachot 97b): a yessod of five tefachim, setbacks of five, horns of five, 58 tefachim in all. Set aside: the Raavad, who suggests setting the horns in from the walls of the altar (on 2:7); the reading of the Semag reported by the Kessef Mishneh (on 2:7), in which each horn rises one ama for an altar of ten.