Approximately 1672 the Huygens barometer was invented by the Dutch physicist Christiaan Huygens (1629-1695) The Huygens tube has a U-shape and contains mercury and an oil-like fluid The contact surface mercury/liquid is enlarged, so that a small difference in the mercury level causes a major change in the oil-like liquid level That’s the reason why the scale of the Huygens barometer is 5 times bigger compared to the Torricelli barometer and the movements in the tube are much more visible ad can be seen at the barometers The Huygens barometer is also called contra barometer because of the opposite direction of rising and falling of the liquid as compared to the Torricelli barometer In addition to this barometer, this version also includes a thermometer and a baroscope (storm glass). It indicates Celsius and Fahrenheit. The frame is finished in wood with brass. Dimensions: 108 cm long, 22 cm wide and 7 cm deep. The object is in very nice condition and completely undamaged and should only be picked up due to its fragility.