Design Concerns and Solutions

Ever since Torricelli's pioneering work, the barometer has been repeatedly re-designed to improve its portability and increase its accuracy.

Dyed spirit or mercury used in early barometers would stain or get stuck in the tube, and, as barometers had an open tube, mercury often spilled out of the instrument during field expeditions. Cistern type barometers were designed to adjust the mercury level for calibration, and were later designed with a plug valve to prevent leakage.

Bending or folding the barometer tube was another solution to reduce the size of the apparatus. Manipulating the glass tube in this way also amplified the movements of the mercury and enabled designers to increase the increments of a marked scale.

Aneroid barometers did not use liquid to measure air pressure. Instead the flexibility of materials such as metal springs bended and distorted shape according to air pressure. Although the concept of an aneroid barometer was first suggested in the early eighteenth century by the German philosopher Gottfried Wilhelm Leibniz (1646-1716), its successful construction was not realized until the mid-nineteenth century.