What is the meaning of "Tachas Lo"?
Radak #1: "Lo" refers to the Safah (brim), like it says in Melachim I, 7:24 "mi'Tachas li'Sefaso." Safah is usually feminine, but sometimes it is masculine ? "Safah Yihyeh l'Fiv" (Shemos 28:32).
Radak #2: "Lo" refers to the Yam.
What surrounded the Yam?
'Rashi': The verse does not say here, but it says in Melachim I, 7:24 that they were Peka'im 1 , i.e. ornamental knobs like people put on cups.
Others say that the shapes of cattle surrounded it; they explain why it says Peka'im in Sefer Melachim. Refer to Melachim I, 7:24:1:2-4 and the note there.
Rashi (Melachim I, 7:24, based on Targum Yonasan): They were the shapes of eggs.
What do we learn from "Eser b'Amah"?
'Rashi': This hints that the three bottom Amos were square 1 ; the top two Amos were circular (Eruvin 14b). This is the only way to resolve its volume (refer to Melachim I, 7:26:3:1).
Refer to Melachim I, 7:24:3:2.
Radak (4): Another proof that the bottom was square is from verse 4, which says that three forms of cattle were under it in each of the four directions.
What do we learn from "Yetzukim b'Mutzakto"?
'Rashi': The forms of cattle were molten together with it. They were not soldered on afterwards.
