This is likely the memorandum he mentions in D12326, though if this is the case then six further pages of the MS are missing. It is written as a dramatic dialogue between Boswell and Voltaire and covers topics such as language, religion, superstition, poetry, literature, and painting

A collection of various documents, including: (I) Set of assignats comprising 16 assignats of five pounds from 1793 (Brumaire year II), 11 assignats of ten pounds from 1792, 3 assignats of fifteen sols from 1793, 2 assignats of 10 sous from the fourth year of freedom, 4 assignats of fifty sols, and 1 assignat of twenty-five sols.
(II) Set of autograph documents from Besins & Cie. including a letter from Joseph B. to Napoleon I (Madrid, 1808), a letter from Verlaine, a letter from Malherbe, a codicil from Napoleon, a testament from Racine, a note from Pierre Corneille, a letter from Voltaire to the Count of Laurencin, a letter of resignation from Cardinal de Rohan to Louis XVI, lots from the trial of the necklace (1786), last letter from Louis XVI to the National Convention, a letter from Beaumarchais to the Minister of the Interior, a letter from François I to the Empress, wife of Charles V on the subject of the interview at Aigues-mortes, a letter from Marie-Stuart to Philip II, a letter patent from Charles VII ennobling Jean d’Arc and his family (1429), a farewell letter from Charlotte Corday to her father after his arrest for the assassination of Marat, and some minutes.
(III) A set of four drypoint engravings of Versailles by Laboratoire Galbrun, ‘Bassin de Cérès’, ‘Le Tapis vert’, ‘Temple de l’Ampur'[?] and ‘Maison de la Reine’.
(IV) Les Laboratoires Carlier, ‘La cabinet de Perles’ by Thomas Lawrence, engravings, 1837.
(V) ‘Woman in French painting, 17th, 18th and 19th century’, Les Éditions Nationales, Paris.
(VI) A handwritten letter in English located in Quebec and dated 28 July 1754.
(VII) Certificate ‘To the glory of the great architect of the universe’ dated 23rd day of the 11th month of the year of true light 5826 (1817).

The author notes that the Library of San Giorgio contains copy of a rare book on military architecture by [?] Franceri de Marché, published 1559. They make notes on the location and conditions of paintings, manuscripts and sculpture in Venice, mentioning efforts being made for preservation. They then comment on the Venetian government’s apparent intention to abolish every order of monks in the state and the new roads around Turin. The author describes a visit to Voltaire in Geneva, writing that Voltaire is ‘now employed about a Dictionnaire Encyclopedia. It has got to the letter B’. They conclude with a discussion of their return journey along Loire, noting the industries they encounter and describing a visit to Fontainbleau.