Translation
Then a man said to his fellow man, “Come, let us whiten whites,
Go to footnote numberand let us burn them through burning.” Thus, they had to them white for stone and bitumen slime for mortar.
Paraphrase
Then each man spoke to his neighbor (repeating the words of their great leader who had convinced them to say these things), “Come, let’s use the white clay that is prevalent here and make bricks and bake them in huge ovens instead of in the sun.” By doing this they provided themselves with bricks which served in place of stones for building. However, bricks require mortar, so they used bitumen slime for that.
Footnotes
1: "whiten whites"
The first word used here usually means “to whiten.” The second word in this clause is “white.” Thus, the clause is literally, “Let us whiten some whites.” However, the context is that of building a tower, and we are told that it was a white clay that they used in that region to make bricks. Therefore, as it is used here, the clause should mean “Let us brick bricks.” This type of repetition was used for some type of emphasis including to indicate the scale or difficulty of the task. The same repetitive emphasis is used in the next clause, “let us burn them through burning.”