Note Book VII. Chap. 2. Note (i) — BOOK VII.

[i] We have sufficient Instances of this in Geese, Ducks, &c. whose Wings, (their Bodies being made for the Convenience of Swimming,) are plac’d out of the Center of Gravity, nearer the Head. But the extending the Neck and Heads in Flight, causeth a due Æquipoise and Libration of the Body upon the Wing. Which is another excellent Use of the long Necks of these Birds, besides that of reaching and searching in the Waters for their Food.

But in the Heron, whose Head and long Neck, (although tuck’d up in Flight,) over-balance the hinder Part of the Body; the long Legs are extended in Flight, to counterpoise the Body, as well as to supply what is wanting in the Tail, from the Shortness of it.