H D N. A portion of a Circle, that was Excentrick to the Sun, and greater than the Circle D E B O, which touch'd D E B O, and was confounded with it in the point D.
H N. The two Mock-Suns, in the intersection of the Semicircle H D N, and the Circle S C H N: The midst of which two False-Suns was white and very luminous; and their Extremities towards D I were tinged with the Colours of a Rainbow. The False Sun, mark'd N, was fainter than that, which is mark'd H.
C. The Mock-Sun, all white, and far less shining, than the two others.
I. A space very dark betwixt R. and D.
* Those Five Suns, that appear'd the 29 March, A. 1629. at Rome, between 2 or 3 of the Clock, in the afternoon, were thus posited; that the two of them, which were in the intersection of two Circles, appear'd in that of a Circle, which passed through the Sun's Diske, with another, that was Concentrick to the Sun: as may be seen in Figure III. borrow'd (for the easier comparing them together) out of Des-Cartes his Meteors, cap. X.
This Appearance is look't upon as one of the notablest, that can be seen, by reason of the Excentricity of the Circle H D N, and because that the Parhelia * were not in the Intersection of the Circle D E B O with the great Circle S C H N, but in that of the Semi-circle H D N.
As for the two odd Rainbows; they appear'd at Chartres the 10. of August, 1665. about half an hour past six in the Evening; and did cross one another almost at right Angles, as may be seen by Fig. IV.
The Rainbow, which was opposite to the Sun, in the usual manner, was more deeply colour'd, than that, which cross'd it; though even the Colours of the first Iris were not so strong, as they are now and then seen at other times.
The greatest height of the stronger Rainbow, was about 45. degrees; the feebler Rainbow lost one of its Legs, by growing fainter, about 20 degrees above the stronger; and the Leg below appear'd continued to the Horizon.