"I suffered like a metal being cast." This line presents the idea of being molded from a
molten, unformed state into something solid. The idea of being cast like a metal is refering to metal when it is
in a liquid state. It is dumped into casts, so that it may be forged into something useful. Frost is comparing this process of molding of metal to the molding of man. Man in his
youth has the potential to become whatever his will may desire. However, just as is the case of the metal, a mold is needed
so that it may become of use.