There is a nearly identical clock in the Rothschild collection at Waddesdon Manor (accession no. 306.1997). The inscription on the present example and the example at Waddesdon Manor are from Book 1 of Imagines by the Greek philosopher Philostatus of Lemnos (c. 190-230 AD). The inscription translates from the Greek as follows: "Whosoever scorns painting is unjust to truth; and he is also unjust to all the wisdom that has been bestowed upon poets—for poets and painters make equal contribution to our knowledge of the deeds and the looks of heroes." Our thanks to Dr. Mia Jackson of Waddesdon Manor for her assistance in translating and identifying this inscription.
Also compare the example sold Christie's, Luttrellstown Castle (Ireland), 26-28 September 1983, and the example at Rosecliff in Newport, Rhode Island (PSNC.1386). See R. de Plinval de Guillebon, Les Biscuits de porcelaine de Paris, Dijon, 2012, p. 214 for an adapted version of the figure of Cupid, here in the guise of Apollo.