A late 17th Century English single handed alarm with calendar in fine silver and tortoiseshell pair cases. Deep full plate fire gilt movement with four tulip pillars and one engraved pillar. Fusee and chain with worm and wheel barrel setup between the plates. Small offset going train with gilt wheels, the hand driven by a small pinion on the fusee arbor. Plain steel balance. Pierced and engraved bridge cock, pierced and engraved plate for the silver regulator disc. Blue steel stopwork for the alarm train, blue steel mainspring visible through the pierced and engraved resting barrel. Steel two headed alarm hammer striking on a bell in the case, steel contrate and crown wheel. Silver champleve dial with Roman numerals the hour indicated by a small blue steel marker on the central alarm disc. The alarm time set by the small double ended blue steel hand. Date calendar marked in Arabic numerals on a gilt ring bordering the dial indicated by a small pin which moves continuously. Pierced and engraved silver inner case, split bezel, silver pendant and ring bow, circular silver shutters to the winding apertures. Fine outer case with silver bezels covered in tortoiseshell. Geometric silver pique pins in the centre of the back surrounded by a band of fine pique pins set in semi-circles encompassing silver rings to allow the bell to sound clearly.