^{page 22 note *} Philosophical Magazine, vol. xxxii., p. 103.

^{page 22 note †} Ibid., vol. xxxii., p. 104–105.

^{page 23 note *} Ibid., pp. 101–2.

^{page 24 note *} Ibid., pp. 106–7.

^{page 26 note *} It may be proper, in order to explain the different values for the same line of the spectrum in the different sets of observations, to remark that these were made on different days, and on flames of different dimensions.

^{page 27 note *} This flame might be used for household purposes, and probably also with advantage in experiments where an invariable source of light is wanted. The liquids, although both smell disagreeably, emit no perceptible odour in burning.

^{page 27 note †} Each number in this and the following table is a single micrometer reading.

^{page 27 note ‡} The observations in this and the following table, on the various lines of the spectrum, were made in the order of the numbers I., II..... VI., in order to eliminate the effect of any gradual change in the dimensions of the flame.

^{page 28 note *} These dimensions were derived from the numbers in the preceding tables by multiplying by 0.0016, the value of a micrometer division in inches; and that was ascertained by observing an accurate inch ivory scale placed in contact with the slit through which the flame was viewed.

^{page 30 note *} Edinburgh Transactions, vol. xxi., p. 71.

^{page 31 note *} Philosophical Magazine, vol. xxx., p. 349.