A Brief relation of the proceedings of the High Court of Justice against Sir Henry Slingsby and Doctor John Hewet, : who for treason against His Highness the Lord Protector, and the Commonwealth, in plotting and contriving a new and bloody war, by bringing in Charles Stuart into this nation, were both beheaded on Tower-Hill, on Tuesday the 8th of this instant June. : Also their last speech and confession at the said place of execution.