-   **April 9, 9:30:** 3 circles in the sky, a very large one of D 100°, center near the zenith, a 4th much smaller. [\[Journal des savans, XIX, Monday 10 May 1666 p. 452; letter of P. Le Bossu, regular canon, abbey of Saint Chéron-lez-Chartres\]]{.source}