Conversation notes pertaining to a meeting with Christiaan Huygens in the Netherlands. Entry for 16 May 1693, following a jotted chapter citation (see note) and a squib about the glass used in microscopes, is an agenda for the discussion topics, which are to include foliate curves, Huygens' dioptrics (laws of refraction), compound 'astroscopes', gravitational theory of (his Oxford colleague from Switzerland,) Fatio de Duillier, a celestial-motion machine, a new pendulum for Huygens' 'horologium' (see Coll-33/Quarto A [4]), centrifugal and centripetal forces in physics, and (the work of) the Frenchman Guillaume de l'Hôpital (who had sent Huygens a paper on foliate curves the previous year). Entry for 18 May 1693 is merely a jotted man's name, one D: Dionyseus Raedts (?) Heer van Brabant. Entry for 17 May 1693 on overleaf, merely the proceedings of the conversation; this includes an allusion to a published version of de l'Hôpital's and Huygens' correspondence on the foliate curve, in the 'journ: des Scavans 1692', by which he must mean 'L'histoire des ouvrages des scavans'. At the bottom of this page, upside-down, and in an unfamiliar hand (Huygens'?) is a piece of verse, referring to the planets and the French.