608 REPORT— 1897. 



Again 

 Pb4. + 1 + heat = rbloichrome yellow, much more volatile than the oxide or sulphide. 



Assay is black. 



+ KjS = PbS brownish black with red edges (lodosulphide ?) 

 — > 



+ HCl = partly removed. 



— > 

 + H.,S04 = changed to yellow. 

 — — > 

 + KSCN = a black ring. 



> 



+ H,,0 = coating removed. 

 + KON= „ 

 Selected equation. Pbl,; + K,S = PbSj, + 2KI. 



Heat toning of equation h.f. of PbS + 2 (801.30) -"^38900 + lOlSW) = h.f. of PbS + 

 19260 calories. 



2. Report on the Teachin{) of Science in Elementanj Schools. 

 See Reports, p. 287. 



3. Report on Wave-length Tables of the Spectra of the Elements. 



See Reports, p. 75. 



4. Interim Rep)ort on the Proximate Chemical Constituents of the 

 various kinds of Coal. 



5. Report on the Action of Light upon Dyed Colours. 

 See Reports, p. 286. 



FRIDAY, AUGUST 20. 

 The following Papers were read : — 



1. Helium. By Professor W. Ramsay, F.R.S. 



2. Contributions to the Chemistry of the Rare Earth Metals. 

 By Professor Bohuslav Brauner, Prague. 



