The quote reflects the author's perspective on the old aristocracy, particularly the Cavalcanti family, who are likened to ancient military commanders and leaders. The speaker suggests that these families have carefully safeguarded their wealth over generations, passing down secrets of hidden riches only to their firstborn sons. This secretive transmission of wealth contributes to their continued opulence.
Furthermore, the imagery of their "yellow and dry appearance" symbolizes their closeness to wealth and suggests that their long-standing fixation on material riches has affected their very being. Just as the florins of their republic appear aged from constant viewing, so too have these nobles become defined by the wealth they hoard, highlighting a deep connection between their identity and their hidden fortunes.