The wall that was broken. Isa. 22:9, 10 mentions many breaches in the wall of the City of David, which were repaired by breaking down houses and using the materials to strengthen the wall.
Another wall without. This was probably an additional wall outside the aqueduct and the City of David, that enclosed the Pool of Siloam. Isa. 22:11 mentions the “ditch between the two walls.”
Millo. The exact nature of Millo is not known, but it must have been a part of the fortifications of Jerusalem, probably a particularly strong place of defense within the ancient city (see 2 Sam. 5:9; 1 Kings 9:15, 24; 11:27).
Darts. Heb. shelach, “something let loose,” or “something sent.” The term may properly mean any weapon that is cast, whether “darts,” spears, or other missiles.