APPENDIX B. 513 



one specimen, made by my friend Mr. Heathcote Wyndham, shews 

 how small a proportion of oxide is sufficient to stain the stone : 



Analysis of Red Sandstone (from Ardrossan). 



QUALITATIVE ANALYSIS. 



Silica. 



Copper (?) trace. 



Iron. 



Aluminium. 



Calcium. 



QUANTITATIVE ANALYSIS. 



Silica, 96*4 per cent. 

 Iron, -364 to -369. 



The aluminium was in excess of the iron. 



THAMES WATER. (See p. 488.) 

 Analysis of Thames Water collected at Oriel Barge. 



Per-centage of solid matter in sample filtered from suspended 

 matter and dried at 100, -02924* = s ^ . 



a This would contain the inorganic matter, calcium salts, &c., and organic matter. 



