Liquid Carbon Dioxide in Thilorier's Apparatus: Baking Soda and Sulphuric Acid Under Their Own Pressure (Sloane, 1899)

Carbon dioxide liquefied by nothing but its own pressure: the gas is made from baking soda and sulphuric acid in one closed vessel and driven into a second, where it gathers as a liquid. Five to seven charges give about 4 litres of liquid carbon dioxide. This is a pressure apparatus. With about 1 litre of gas space in the charged generator, the pressure rises to 100 atmospheres at 40 °C. A cast-iron apparatus of this kind burst in Paris in 1835 and killed the assistant; cast iron was then forbidden, and the improved vessels are lead inside copper, bound with iron hoops. Not given: acid strength, time per charge, how the spent liquor is emptied and how the liquid is drawn off. Source: T. O'Conor Sloane, Liquid Air and the Liquefaction of Gases (1899), pp. 137-140. Picture: Sloane's cut of the apparatus.