CLEMENT XIV, Pope. Interesting Letters of the Late Pope Clement XIV. (Ganganelli.). Newcastle: T. Saint, for W. Charnley, 1777. 2 volumes. 8° (213 x 129mm.). Engraved frontispieces (one a portrait). Contemporary light calf, spines ruled in gilt, red and green lettering pieces. Provenance: Sir James Colquhoun of Luss (armorial bookplate). -- [BOLINGBROKE, Henry St. John, Viscount]. Letters on the Spirit of Patriotism. 8° (202 x 116mm.). Half-title. Contemporary calf, gilt spine, red lettering piece, red sprinkled edges (short crack in lower hinge). Provenance: Walter Ogilvy (signature on title-page). First authorised edition. Rothschild 417. -- FITZOSBORNE, Sir Thomas. The Letters...on Several Subjects. 8° (202 x 125mm.). Contemporary calf, spine ruled in gilt, red lettering piece (spine a little discoloured); and 4 others (Lyttleton's Letters, 1782; Montague's Letters, 1793; Clement XIV's Interesting Letters, 2 volumes, 1777).