BETWEEN MURIATIC ACID AND CHLORINE. 351 



hygrometrically dry. Unwilling, however, to shelter myself 

 behind such an apology, I have thrice made the experiment 

 with this acid gas, and have obtained each time a most satis- 

 factory result. 



Pure iron turnings were introduced into a green glass tube 

 about 4 feet long ; and they were made to occupy about 6 

 inches of it, near one end. To this was luted, the tube of conv 

 munication with the mercurial trough. The part containing 

 the turnings, rested on the semicylinder of iron, within the fur- 

 nace. To the other end, which was about 3 feet from the furnace, 

 the beak of a tubulated retort was luted. Into this, which con- 

 tained dry muriate of soda, and which was furnished with a sy- 

 phon-tube of safety, concentrated sulphuric acid was slowly drop- 

 ped. The projecting green glass tube, with the neck of the re- 

 tort, altogether about four feet long, were surrounded with pa- 

 per kept moist with ether, as was also the tube of communica- 

 tion, on the other side, with its bulb. As soon as I found that 

 the gas escaping in the pneumatic trough was muriatic acid, 

 free from admixture with common air, the charcoal furnace 

 was kindled. The heat being gradually raised to bright igni- 

 tion, whilst the acid gas was slowly disengaged, in the cold 

 retort, I found at the end of a short period, that liquid was 

 condensing in the bulb, though no traces of moisture ever ap- 

 peared within the long tube, between the retort and the fur- 

 nace. The moisture increased in a very slow, but regular pro- 

 gression. At the end of three hours the quantity had become 

 considerable. In one case, it amounted to nearly 6 grains. It 

 was liquid muriatic acid. During the whole process, hydrogen 

 and muriatic acid gases escaped through the mercury, in the 

 proportion, by volume, of 13 of the former to 1 of the latter. 



This acid gas, as it issues hot from the furnace, is very apt 

 to take up the deposited moisture, unless we screen the tube 



from 



