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



red before the gas liquefied, but did not dissolve or otherwise alter in the 

 liquid acid. Sesquioxide of uranium became of a paler yellow colour in the 

 gas, but did not dissolve in the liquid acid in six days ; the residue was 

 entirely soluble in water. Precipitated black oxide of manganese in powder, 

 and free from water, became quite white in the gas ; it remained white in 

 the liquid acid without evolving visible bubbles of gas, and did not lessen in 

 bulk in seven days. A crystal of permanganate of potash softened and 

 swelled in the liquid acid, but did not dissolve in five days ; it remained of a 

 dark colour ; the residue placed in distilled water produced no coloration. 



A crystal of metallic arsenic remained perfectly bright and unchanged 

 in bulk during three days' immersion. Arsenious acid in powder quickly 

 liquefied in the gas, and dissolved to a colourless solution in -the liquid 

 acid. A crystal of arsenic acid softened before the gas 'liquefied, and 

 dissolved quickly and freely in the liquid acid to a colourless solution. 

 Bisulphide of arsenic in powder did not dissolve in six days, but became 

 slightly less red and more yellow ; a slight yellowish-white sublimate oc- 

 curred in the tube during the generation of the gas. Teriodide of arsenic 

 in powder slightly dissolved to a purple-red liquid ; apparently only a trace 

 of its iodine was extracted, as its bulk was not visibly less in three days. A 

 crystal of bright antimony remained perfectly bright and unchanged after 

 nine days' intermittent immersion. Precipitated teroxide of antimony 

 became partly liquid before the gas liquefied ; it dissolved in the liquid 

 acid quickly and rather freely, and made a colourless solution. A frag- 

 ment of precipitated antimonic acid did not dissolve in six days. A frag- 

 ment of black tersulphide of antimony evolved a film of yellowish- white 

 sublimate, and lessened in bulk before the gas liquefied ; it decomposed and 

 dissolved in the liquid acid in about a quarter of an hour, and formed a 

 colourless solution which exhibited no further change during seven days. 

 A fragment of bright metallic bismuth remained undissolved and un- 

 changed in the liquid during three days. 



Bright zinc evolved no visible gas in the liquid acid, and was not per- 

 ceptibly corroded in three days. Oxide of zinc slowly dissolved in seven 

 days. Metallic cadmium evolved no gas in the liquid, and was not 

 sensibly corroded in three days. Precipitated carbonate of cadmium 

 evolved no visible gas in the liquid acid, and remained undissolved and 

 unchanged in appearance during seven days. Yellow sulphide of cadmium 

 evolved a trace of white sublimate before the gas liquefied ; in the liquid 

 acid it became quite white, and remained undissolved in seven days ; on 

 removal it was hard in texture and quite white throughout, and evolved no 

 odour of sulphuretted hydrogen or separation of sulphur on treatment with 

 strong nitric acid. Bright tin evolved no visible gas in the liquid acid ; 

 after ten days' intermittent immersion it was converted, to some depth of 

 its substance, into a bulky white solid with deep fissures. In a second expe- 

 riment of three days' immersion, similar results occurred ; all the tin was 

 corroded except a minute fibre in the centre, the white solid was imper- 





