Beneath the practical plot details, the symbolism of the silver continues. These
laborers are so happy in their fidelity to the rulers that they actually sing
while being towed back and forth to their job (a symbolic towing by the material
interests that recalls Ribiera's ).
Note the nature of a "chorus," being a collective which plays a backup
role to the protagonist (i.e., the ruler). Note also the subtle phrasing in which
the lighters are "empty" without their material load, despite being
filled with men. Laborers who sing through such exploitation would indeed have
no occasion to approach the symbolic silver of independent worth.