212 Mr. G. Gore on the Properties of [May 4, 



in the gas ; it evolved no gas in the liquid acid, and was only slightly cor- 

 roded after seven days. Black oxide of copper became of a lighter colour 

 in the liquid acid, but did not lessen in bulk in seven days ; the residue 

 was a greenish and yellowish white powder, which instantly turned black 

 in water, forming a pale-blue solution, and left black oxide of copper. A 

 crystal of blue vitriol became of a light brown colour in the liquid acid, 

 but did not dissolve in six days ; on removal it was found to be a brown 

 soft solid. Protoxide of mercury became white in the gas, and did not 

 dissolve by constant immersion in the liquid acid iu four days ; the residue 

 was a white solid, soluble in water. Vermilion in powder slowly changed 

 in the liquid acid in three days to a pinkish-white solid, but did not dis- 

 solve. Scarlet iodide of mercury in powder imparted a red colour 

 to the liquid acid, but did not lessen in bulk or change in colour 

 during three days ; the residue lost its red colour on the application of 

 heat. A fragment of protochloride of mercury did not visibly alter in the 

 liquid acid in four days. Metallic silver did not dissolve or become much 

 corroded during seven days. Oxide of silver became white in the liquid 

 acid in one day, but did not dissolve. Precipitated chloride of silver iu 

 powder did not visibly alter or dissolve during sixteen days. Metallic pla- 

 tinum was unaffected in the liquid acid. 



Oxalic acid was slightly dissolved in the liquid acid in three days with- 

 out change of colour. Uric acid remained undissolved and unchanged 

 during three days. Paraffin did not appear to be dissolved or affected in 

 nine days. Gutta percha was quickly acted upon ; it imparted to the liquid 

 acid, first a red, and ultimately a dark-brown colour ; it appeared also to 

 dissolve in the acid to some extent, and on discharging the tubes was left 

 behind as a tenacious coating upon the adjacent parts. Gun-cotton was 

 unaffected in the liquid acid. Cotton was not visibly altered in two days. 

 Solid extract of litmus dissolved slightly, forming a faintly purple blue or 

 inky solution ; it became of a dark red colour and enlarged in bulk ; the 

 residue formed a perfect solution in water ; the solution was red in colour. 



Remarks. The foregoing experiments show that liquid hydrochloric acid 

 has but a feeble solvent power for solid bodies in general. Out of 86 solids 

 it dissolved only 12, and some of those only in a minute degree; of 5 

 metalloids it dissolved 1, viz. iodine; of 15 metals it dissolved only 1, 

 viz. aluminium ; of 22 oxides it dissolved 5, viz. titanic acid, arsenious 

 acid, arsenic acid, teroxide of antimony, and oxide of zinc ; of 9 carbonates 

 i t dissolved none ; of 8 sulphides it dissolved 1, viz. tersulphide of anti- 

 mony; of 7 chlorides it dissolved 2, viz. pentachloride of phosphorus 

 and protochloride of tin ; and of 7 organic bodies it dissolved 2. 



The results show also that liquid hydrochloric acid in the anhydrous 

 state manifests much less chemical action upon solid bodies than the same 

 acid when mixed with water as under ordinary circumstances ; for instance, 

 the difference of its action upon magnesium, zinc, cadmium, and even 

 aluminium, under the two conditions, is very conspicuous. This may 



