Pocket thermometer: very fine and extremely rare pocket thermometer in manner of Houriet, attributed to Courvoisier & Compagnie, ca. 1830: Ca. Ø59mm, ca. 69g, silver, engine turned, in fantastic condition, No.5822, perfectly preserved and sensationally rare enamel dial showing exceptional registered temperatures and the corresponding dates from 1709-1788, steel hands, in fantastic condition. We know of only 3 of these pocket thermometers, all identical and with the same dial. These are the present piece, another example in a Parisian private collection and the more famous signed example, auctioned in Geneva for 12,650 Swiss Francs, formerly part of the Theodor Beyer collection. About the history of this museum thermometer: Louis Courvoisier's second wife was Julie Houriet, a niece of Jacques Frédéric Houriet, the inventor of the bimetallic thermometer. The relationship between Courvoisier and Houriet was not only limited to family relations as the present thermometer proves. It is based on Houriet's design, with slight differences in the micrometric setting mechanism and the dial, which has unusual indications that give the appearance of being the years of recorded temperatures.