The Planet Saturn. 197 



II., and Nov. 4. 15, Lassell, the shadow had changed sides, 

 and the "sudden projection" lingered as a similar spot p, so 

 that there was shadow, though on B only, on both sides of the 

 ball. In this month De la Rue drew the shadow /, with a 

 strong discontinuity at the division, as though A lay above B 

 (inverted). 29, on both sides, much plainer/; "This is very 

 remarkable, but there can be no question as to the fact :" both 

 like objects seen by mirage: B. I. See the diagram, Fig 1. 

 The American memoir contains no less than 40 views in which 

 some peculiarity of the shadow is represented, from which 

 Figs. 1, 2, 3, 5, 6, 7 have been selected, with regret at the 

 omission of many others equally curious, especially as the 

 work is very little known in England. Dec. 1, p shadow 

 seems to adhere to and partially overlap limb ; in continuation 

 of a dusky belt, but much darker: B. II. — 1853, Jan. 8, a 

 singular dusky spot adhering to p limb, as often before ; _/ 

 shadow almost makes a corner opposite to it, at Ball's div. : B. 

 II. Oct. 24, 25, Nov. 2, Dawes saw little triangular spot /, 

 just within division, considerable breadth of shadow p, concave 

 to limb on B, convex* on A, and much further out on B than 

 A, so as to make a notch at division, as though in two planes. 

 [His drawing singularly like our Fig. 1, but reversed, and 

 placing the small spot close to the division.] — 1854, Feb. 12, 

 and later, Hippisley observed the shadow on B conspicuously 

 concave towards the ball, so that it should have passed over 

 much of A, if in the same plane ; this ring, however, was 

 untouched : it seemed as though B had a convex surface. 

 From computation and experiment he found that, allowing for 

 polar flattening (which is material), the shade on A would 

 have been hidden by the ball, especially if A were in the least 

 above B. But he does not allude to the reversed curvature. 

 Sept. 26, p shadow on B nearly straight; 29, a little recurved, 

 with a small projection f close to division : Dawes. Nov. 23, 

 S. region of globe (now coinciding with Ball's div.), or adjoin- 

 ing part of ring, singularly distorted. On each side of globe a 

 slight shading on B, turning out right and left in 2 corners along 

 division, which is quite fiat between them : B. II. ; Coolidge, 

 with 5 ft., ditto. Nov. 26, Dec. 7, angular projection on both 

 sides, up to Ball's div., something like our Fig. 2, but equally 

 black and blunted on either hand. A unshaded : Dawes. 9, 

 flattening of S. regions very evident : B. II. Later, and much 

 finer air, a new distortion ; horns of the two shadows certainly 

 concave : S. edge of shadow (or Ball's div.) between them 

 straight, and ball at S. edge encroaching in a protuberance 



* The terms are occasionally interchanged by observers, the outline being 

 sometimes referred to the enlightened, at others to the shaded part of the ring. 

 The latter is always preferred here. 



