sentences:  It was his first piece played in a concert.In March 1873, his Czech patriotic cantata "The Heirs of the White Mountain" was performed by the Prague Hlahol Choral Society of 300 singers (conducted by his friend and supporter Karel Bendl) to a warm response from both audience and critics, making it an "unqualified success".Dvořák's compositions were first coming to be recognized in Prague.