Swiss double-sided decorative calendar watch Circa 1880

Gold calendar watch with moon phase
–
A rare, double-sided Swiss calendar watch with moon phase, patent Calendrier Breveté SGDG, circa 1880.
Frosted gilt bridge movement, Swiss lever escapement, screw compensation balance. Two dials: enamel front dial with Roman radial hours, outer minutes track with Arabic five minutes numerals, subsidiary dial for the seconds, and blued steel pear hands;  silvered back dial with an extraordinary calendar,  indications of the date and weekdays, rectangular aperture for the month, and large moon phase in the centre. 14K red gold case with on the cuvette the 12 months indicated in French with the number of days of the month.
–
Diameter: 50 mm
–
Weight: 92 g
–
Signed: Calendrier Breveté SGDG
–
Certification SGDG, Abbreviation for Breveté Sans Guarantee Du Gouvernement
Breveté Sans Guarantee Du Gouvernement is a patent or utility model protection. Translated: patent without a government guarantee.
In 1844 a law was enacted in France whereby patents could be issued without prior examination, at the applicant’s risk and risk and with no guarantee of function, novelty and merit on the invention, also about precision or accuracy of the description. This legal opinion remained valid in France, it’s country of origin, until 1968.
Other countries stuck to such a system of registration after a simple formal examination for many years. This should exclude liability claims of any kind.