Note on page 59 * I have often wished for the liberty to abbreviate the word "Aeroplanes" in this way, and since the meaning is not obscured by the shorter term, I trust it, or some other short term, may come into use.

Note on page 60 * I adopt “drag,” i:he word suggested by Mr. Archibald Low, in preference to the word "drift" to express the "resistance to forward motion through the air." The word driit is badlv wanted in aeronautics in its own time-honoured significance, so that the actual travel of an aircraft maybe compounded of the distance which it travels axially, and its drift, i.e., the amount it drifts with the wind,

Note on page 63 * Much on the lines of the Wright stabiliser is that described in Pat. 10,424, April 29, 1909. (Motorluftshiff. ) The speed of the aeroplane is regulated by an elevator controlled by the air-pressure acting on a membrane to steer up when speed rises and down when it diminishes. The Wright plane; was horizontal, however.

Note on page 63 † Whether this swing back is accompanied by oscillations or not, is, it will be observed, entirely overlooked in this—as was indicated in para. 1 above.

Note on page 63 † Alternative methods of looking at this are to be found everywhere, e.g.., the author's paper on Aircraft Problems. Proceedings Inst. Autom. Engineers, March 1911, p. 285, where the righting couples are calculated for various cases which have been kept simple by assumptions which are set forth.

Note on page 63 † I ventured in 1911 to call this "S" type after Santos Dumont, the originator, or at least the first successful flyer, with this type. “Tail-first” is a misnomer and misleading. "Canard" or Duck is legitimate.

Note on page 68 * I have since learnt that л somewhat similar idea was evolved bv Mr. Hulbert in U.S.A.