Translation of "Doorposts" in Portuguese

Close cling their ladders to the walls; these, fain / to clutch the doorposts, climb from floor to floor, / their right hands strive the battlements to gain, / their left with lifted shield the arrowy storm sustain.

Encostam no alto das paredes, / de ambos os lados da soleira, escadas, / que vão logo trepando. Enquanto o escudo, / ao braço esquerdo preso, os projéteis apara, / a mão direita estende-se buscando / agarrar os degraus mais elevados.