Strontium salts may be recognized by the characteristic crimson colour they impart to the flame of the Bunsen burner and by the precipitation of the insoluble sulphate.
By this method even such metals as iron and copper may be made to show some of their characteristic lines in the Bunsen burner.
If a short length of platinum wire be inserted vertically into a lighted Bunsen burner the luminous line may be used as a slit and viewed directly through a prism.
Thus one of the most common spectra is that seen at the base of every candle and in every Bunsen burner.
Young, according to which the dark line observed in the centre of each component of the sodium doublet in a Bunsen burner is transparent to a radiation placed behind.