coloured Films formed by Iodine, fyc. upon Metals. 433 

 Bromine with Silver and Copper. 



5th change. Copper 

 Silver 

 Copper 

 Silver 

 Copper 

 Silver 

 Copper 

 Silver 

 Copper 

 Silver 



sensibly darkened. 



unchanged. 



deep red. 



unchanged. 



red, blue. 



pale gold. 



white, orange of the 2nd order. 



yellow. [order. 



green of the 1st order, red 3rd 



blue. 



Chlorine with Silver and Copper. 

 The affinity of chlorine with silver is much inferior to that 

 which it possesses for copper. 



Iodine with Titanium. 

 Iodine at the common temperature has no action upon this 

 metal. 



Bromine with Titanium. 



Bromine, when the surface of this substance is perfectly 

 dry, has no more action upon it than iodine; but if it have a 

 slight coating of moisture, as is formed by merely condensing 

 on it the vapour of the breath, the coloured films are formed 

 without difficulty by the vapours of bromine. Their appear- 

 ance is the same as those of the iodide of silver, viz. gold, 

 deep gold, blue, white, yellow, orange, red, &c. 



Chlorine with Titanium and Copper. 

 Titanium has a stronger affinity than it has for either of 

 the preceding vapours. The combination takes place when 

 the metallic surface is either dry or moist. 

 Copper . . . much reddened. 

 Titanium . . . not affected. 



f passed through several of the spectral or- 

 Copper • • •"{ ders °f re d and green until it arrived at 



[_ almost its last changes of colours. 

 Titanium under the same action received a dull film, which 

 viewed obliquely showed red, green, yellow. 



Silver, exposed to the same influence as the two former, 

 had yellow in the centre and blue more externally. 



Iodine with Bismuth and Silver. 



Silver . . . pale gold. 



Bismuth . . . some parts yellow, others not attacked. 

 Silver . . . blue, white, yellow, orange. 

 Bismuth . . . blue, yellow, orange. 

 Phil. Mag. S. 3. Vol. 21. No. 140. Dec. 1842. 2 G 



