Properties of Liquefied Hydrochloric Acid Gas. 543 



continued a few days ; and in many cases the acid was not in a liquid 

 state the whole of the time, but only at intervals ; in all cases, how- 

 ever, the period of immersion was abundantly sufficient for the 

 liquefied acid to produce its full effect. 



The effects in nearly all cases were of so distinct a character, 

 and the conditions under which they were produced so definite, as 

 not to require repetitions of the experiments ; but those which 

 were in any respect uncertain were repeated, and those also which 

 were of an important or striking character were likewise repeated, 

 in order to remove the least shadow of a doubt that might be raised 

 respecting them. 



The liquid acid is a very feeble conductor of electricity. Two 

 fine platinum wires, immersed in it fths of an inch in length and Yjjth 

 of an inch asunder, and connected with a series of 10 Smee's ele- 

 ments, evolved no perceptible bubbles of gas, and produced only 

 a moderate deflection (amounting to 23 degrees) of the needles of 

 a sensitive galvanometer ; and this amount of conduction might pos- 

 sibly have been due to a minute trace of oil of vitriol mixed with 

 the liquid acid. In a second similar experiment, with the wires 

 -^g-th of an inch apart, not the slightest conduction occurred on 

 using the same battery-power, but by employing the secondary cur- 

 rent of a strong induction-coil with condenser attached, conduction 

 and a steady deflection of the needles of the galvanometer (26 

 degrees) took place, gas being freely evolved from the negative wire 

 only. On separating the brass points of the secondary terminals 

 beyond the distance of the thickness of a thin address card, sparks 

 ceased to pass between those points, and gas was evolved copiously 

 in the liquid acid, apparently in the mass of the acid between the 

 two platinum wires as well as at the wires themselves ; two similar 

 platinum wires in dilute hydrochloric acid in the same circuit evolved 

 very little gas. It is probable that much of the gas evolved in the 

 liquefied acid was not a product of electrolysis, but simply the acid 

 itself volatilized by the thermic or other action of the current. No 

 sparks occurred at any time in the liquid acid. It is evident there- 

 fore that liquefied hydrochloric acid gas is a very bad conductor of 

 electricity, but it is not nearly so powerful an insulator as liquefied 

 carbonic acid gas. 



The following experiments illustrate its chemical, solvent, or 

 other action upon various substances immersed in it. The quantity 

 of the solid substances employed was in nearly all cases very small 

 in proportion to that of the liquid acid in contact with them, and 

 in many cases did not amount to one-twentieth of its volume. 



A piece of charcoal remained unchanged at the end of ten days, 

 the acid being in a liquid state in contact with it at intervals. A 

 fragment of fused boracic acid did not lessen in bulk or alter in 

 appearance in seven days. White phosphorus was undissolved and 

 unchanged in nine days, and remained equally inflammable. A 

 fragment of ordinary sulphur did not dissolve or alter in several 

 days. Fragments of vitreous black selenium did not dissolve or 

 change in six days. Iodine dissolved rather freely, and quickly 



