John Locke. Stipple engraving by R. Cooper after G.B. Cipriani.

The cap of liberty etched below the portrait is a mark of association with Thomas Hollis, who had commissioned the print: "He had moreover procured to be engraved the beautiful head of the author by Signor Cipriani. The same artist had engraved for him the head of Locke to be prefixed before the new edition of the treaties on government published in 1763" (Blackburne, loc. cit.). Hollis was a republican and promotor of civil liberties. The two works by Locke that were edited and published by Thomas Hollis--The two treatises of government (London 1764) and Letters concerning toleration (London 1765)--were part of Thomas Hollis's 'Library of Liberty' which he distributed to libraries and individuals across Europe and America in the 1760s and 1770s