Combined barometer and thermometer, 1719.
© Science Museum / Science & Society Picture Library
In the bottle tube type of mercury barometer, the tube includes an open bulb at the lower end to act as a reservoir for the mercury. Half a century after the original experiments by Torricelli, the barometer was a decorative piece of furniture. Isaac Robelou of London decorated this one in the Chinese style, and with an extra spirit thermometer.