Analemmatic Sundial Signed F. Briot And Dated 1739

Analemmatic sundial in pewter and brass in a shaped wooden case.
The dial is composed of two plates: one oval and the other octagonal, the latter sliding on the former.
The oval plate corresponds to an analemmatic dial with its IV-XII-VIII graduated hour scale and the signature “F. Briot” in the centre. 
The sliding upper plate has a graduated IV-XII-VIII time scale with the date “1739” at the lower end. A folding brass gnomon tops the plate. One of the gnomon’s attachments is decorated with flowers.
The case is in black stained wood to the form with brass hinge and the interior lined with polychrome embossed paper with floral decoration.
Dimensions: 
– Case: length 9.7 cm x width 10.2 cm
– Dial: length 8.3 cm x width 8.8 cm
France dated 1739.