1823.] of several Gases into Liquids. 89 



easily assisted by artificial cold in cases when gases approach 

 near to that point of compression and temperature at which 

 they become vapours. 



On the Condensation of several Gases into Liquids *. 

 [Read April 10, 1823.] 



I HAD the honour, a few weeks since, of submitting to the 

 Royal Society a paper on the reduction of chlorine to the 

 liquid state. An important note was added to the paper by 

 the President, on the general application of the means used in 

 this case to the reduction of other gaseous bodies to the liquid 

 state ; and in illustration of the process, the production of 

 liquid muriatic acid was described. Sir Humphry Davy did 

 me the honour to request I would continue the experiments, 

 which I have done under his general direction, and the follow- 

 ing are some of the results already obtained : 



Sulphurous Acid. Mercury and concentrated sulphuric acid 

 were sealed up in a bent tube, and, being brought to one end, 

 heat was carefully applied, whilst the other end was preserved 

 cool by wet bibulous paper. Sulphurous acid gas was pro- 

 duced where the heat acted, and was condensed by the sul- 

 phuric acid above ; but when the latter had become saturated, 

 the sulphurous acid passed to the cold end of the tube, and 

 was condensed into a liquid. When the whole tube was cold, 

 if the sulphurous acid were returned on to the mixture of sul- 

 phuric acid and sulphate of mercury, a portion was reabsorbed, 

 but the rest remained on it without mixing. 



Liquid sulphurous acid is very limpid and colourless, and 

 highly fluid. Its refractive power, obtained by comparing it in 

 water and other media with water contained in a similar tube, 

 appeared to be nearly equal to that of water. It does not soli- 

 dify or become adhesive at a temperature of F. When a 

 tube containing it was opened, the contents did not rush out as 

 with explosion, but a portion of the liquid evaporated rapidly, 

 cooling another portion so much as to leave it in the fluid state 

 at common barometric pressure. It was however rapidly dis- 

 sipated, not producing visible fumes, but producing the odour 

 of pure sulphurous acid^ and leaving the tube quite dry. A 



* Philosophical Transactions, 1823, p. 189; also Phil. Mag. Ixii. p. 416. 



