In addition to these religious and political differences, both the lower-class rioters and their upper-class Anglican leaders had economic complaints against the middle-class Dissenters. They envied the ever-increasing prosperity of these industrialists as well as the power that came with that economic success. Historian R. B. Rose refers to these industrialists as belonging to "an inner elite of magnates". Priestley himself had written a pamphlet, "An Account of a Society for Encouraging the Industrious Poor" (1787), on how best to extract the most work for the smallest amount of money from the poor. Its emphasis on debt collection did not endear him to the poverty-stricken.