Spectra and Latent Energy in Flame Gases

PROF. W. T. DAVID in the first paragraph of his letter under this title1 makes two points about the afterglow in the gases from names or explosive reactions; the first that the temperatures determined by the sodium flame reversal method are too high, compared presumably with the platinum resistance method, the second that long-lived luminous products account for a considerable proportion of the heat of combustion, while further on he mentions 15 per cent.