To all the affectors and approvers in England : of the London petition of the eleventh of September, 1648, but especially to the owners of it, by their subscriptions, either to it, or any other petition in the behalf of it; and particularly to the first promoters of it, my true friends, the citizens of London, &c. (continuing unshaken in their principles, by offices, places, or other base bribes or rewards) usually meeting at the Whalbone in Lothbury, behinde the Royal Exchange, commonly (but most unjustly) stiled Levellers.