N. B. The Circular View is seen to the best Advantage, when placed flat on a Table or Chair, and rather in the Shade: the Eye looking directly down upon the Picture.
Whoever will be at the Trouble of viewing distinct Parts of the Balloon-Prospect, throu’ a very small Opening, made by rolling a Sheet of Paper into the Form of a hollow Tube, and applying it close to either Eye, at the same Time shutting the other; or by looking throu’ the Hand, held a little open, and close to the Eye; may form a very accurate Idea of the Manner, in which the Prospect below was represented gradually in Succession, to the Aironaut; whose Sight was bounded by a Circularity of Vapour, as in Section [79], [221].
2d. Directions for placing them.
Place the Top of the circular view, even with the Top of the Page.
The Plate will then lye over at the Bottom, and at the right Side of the Page.
Fold the Bottom up into the Book, even with the Margin: and the right Side in like Manner.
Observe to place the Bottom of each of the other Plates, even with the Bottom of the Page.
The Plate will then lye over at the Top, and at the right Side of the Page.
Fold the Top down, into the Book, even with the Margin: and the right Side, in like Manner.
The circular View, to face Page 58.