Barometer - mercury thermometer signed by Engineer Chevallier optician of the king and princes, opposite the flower market no 1 in Paris. Brass and mahogany veneer with a wheel allowing the reading of the barometer. The graduation for the thermometer bears the mention of great temperatures in Paris in the years 1770-1780. Missing the thermometer and three screws of fixing. Some accidents on the veneer. French work, around 1820. H : 105 cm Provenance : Sale at Drouot on October 3rd, 1996.