On the west side the shadow is the thinnest possible line as far as the principal division. On both sides the shadow consists of two parts, bounded by nearly straight lines, which meet at an angle as shown. The CASSINI division is seen quite up to the shadows on both sides.

1879, Oct. 16, about 12h 30m, W. m. t. WVt. 2.

26-inch equatorial.

Figures 3 and 4 are 4 refers to the N. part on the rings is seen on The shadow of the ring

(See Figure 4) [To economize space, drawn on the same form in the frontispiece. of the figure only.] The shadow of the ball both sides. [No drawing made of this.] on the ball is the thinnest possible line, as drawn, thickened at the ends. It looks perfectly straight.

1879, Nov. 3, 12h W. m. t. 26-inch equatorial. Wt. 2-Eyepiece, 600.

(See Figure 5.) Ball: the Southern Hemisphere is nearly all an olive-green and dark. All the rest is bright, and no markings are seen, except one streak in the Northern Hemisphere, as in the sketch.

Rings: They are as usual and as drawn.

Shadow of Ball on the Ring: Convex towards the ball [as is usual when the air is not steady] and broken at the principal division. This division, however, is not seen any further than as drawn.

Shadow of Rings on the Ball. Very dark, and the ends widened, as in the figure.

Dusky Ring: The ends of the dusky ring as seen on the ball at the limbs of the planet [above the rings in the figure] are widened, so that the ends on the planet appear broader (north and south) than the fine ends of the dusky ring [outside the ball] which come up to the limbs and meet them.

The whole dusky ring is not so well seen to-night as before, and it appears really fainter.

hazy.

1879, Nov. 11, 101 W. m. t.

26-inch equatorial.. Wt. 2. Sky

(See Figure 6.) There appears to be a dark patch on the east side of the South Pole, and, possibly, one near to the North Pole, much fainter. The shadow of the ring on the ball is as drawn. The principal division is not seen beyond the points marked.

1880, Aug. 21, 12h 45m to 13h 20m, W. m. t. torial, eyepiece 400, Wt. 3. Sky very hazy.

26-inch equa

(Drawing omitted.) The shadow of the ball on the ring is not so black as the spaces within the ansae. The curve of the edge of this shadow appears to be very slightly convex to the ball. The principal division is seen all around. ENCKE'S division in Ring A is seen near the ends of the ring.

1880, Aug. 24.

26-inch equatorial, eyepiece 400. Wt. 4.

(See Figure 7.) The principal division is seen all around. The ENCKE'S division is as drawn. It divides Ring A into two parts, whose widths are as 1 to 2, and it is nearer the outer ellipse of Ring A. The south hemisphere of the ball is a warm olive color. The edge of the shadow of the ball on the ring is nearly a straight line, but it is a very little convex to the ball, and it is black.

The shadow of the ball on the ring is 2 times wider at its S. edge than at the N.

The grey shading in Ring B extends from the outer ellipse of the dusky ring to of the way to the CASSINI division.

The ends of the dusky ring on the ball [above the rings in the figure] make a little angle where they meet the ends of this ring outside the ball [i. e., the ends on the planet are wider.]

1880, Aug. 26. Time? 26-inch equatorial.

(Drawings omitted.) The shadow of the ball on the ring has about these proportions: west side 3, south side 3, north side 1. 1880, Aug. 27. 26-inch equatorial, Eye-piece 800. (Drawing omitted.)

Wt. 5.

The shadow of the ball on the ring is, on the whole, slightly concave to the ball. The appearance of concavity arises from a break in the outline of the shadow at the principal division. The shadow of the ball is seen on the dusky ring, and leaves a little sharp corner where this shadow meets the inner ellipse of the dusky ring. The outlines of the principal division are smooth all around. There are no notches at the ends, as drawn by M. TROUVELOT in 1874. There is a trace, and only a trace, of ENCKE's division on Ring A, of the distance from the outer to the inner ellipse of the ring. Ring B appears to be composed of three rings, distinguished by the difference of shading. The inner one of the three is the width of Ring B; the two inner ones together are about 1% of this width.

The ends of the dusky ring at the limbs of the planet are wider (north and south) at the limbs than the fine ends of the dusky ring outside the ball which come up to meet them. [This has been previously noted, and may be due to the presence of a narrow, dark

belt on the planet itself, which is not seen separate from the dusky ring crossing the ball.] At the ends of the dusky rings on the ball there is a distinct "step" at the limb.

It is certain that the outline of the ball cannot be seen through the dusky ring on the west side, but I am almost sure that I see it on the east side.

400.

1880, Sept. 2.

12h W. m. t. 26 inch equatorial, Eye-piece

(See Figure 8.) The sketch is not accurate as to all its dimensions, but it gives the relative shapes and general effect correctly. 1880, Oct. 8. 13h W. m. t. 26-inch equatorial. Wt. 3. (Drawing omitted.) Sky not perfectly clear.

The principal division is seen up to within about 4" of the ball, both in front of and behind the planet. The shadow of the ball on the ring on the west side of the planet is bounded by two straight lines, a and b. a is parallel to a tangent to the S. W. quadrant of the outline of the ball near latitude 45°. b makes an angle of 55°-60° with the circumference of the ball near it. a and b meet at a vertex at the principal division. There is a shade on the ball which borders the shadow of the ball on the west end of the ring. There is also a faint beginning of a shadow of the ball on the ring on the east end of the ring.

1880, Oct. 9.

26-inch equatorial, Eye-piece 800.

(See Figure 9.) The shadow of the ball on the ring is seen on both sides of the ball. On the west side, the bounding line of the shadow is a perfectly straight line, and the outer edge of the ring ends in a fine, sharp, cusp point; the effect is, perhaps, as if this boundary was slightly, but very slightly, concave to the ball. On the east side of the ball there is a straight, dark, narrow line of shadow also. The CASSINI division is seen all around. The ENCKE division is well seen of the width of Ring A from its outer edge. 1880, Oct. 10. 26-inch equatorial, Eye-piece 800, Wt. 4. (See Figure 10.) The southern hemisphere of the ball is olivecolor. There are two shades or blurs on the ball bordering the shadows of the ball on the ring (which are on both sides).

The shadow of the ball on the ring on the west side is o".23 thick at its north end, and o".35 at its south end. The shadow of the ball on the ring east of the ball is o".23 thick. The dusky ring is suddenly wider as it crosses the ball. The principal division is perfectly smooth all around [no notches in it.] ENCKE's division is seen of the width of Ring A from its outer ellipse.

1880, Oct. II.

26-inch equatorial, Eye-piece 600, Wt. 5.

(See Figure 11.) The shadow of the ball on the ring on the west side is very narrow at its north end, and a very little wider at its south end. The bounding line is nearly straight, but just perceptibly concave to the ball. The shadow of the ball on the east side is narrower than that on the west, and it appears very slightly convex to the ball. The shadow of the ball on the dusky ring is seen on the east side [only.] I cannot see the limb of the planet through the dusky ring. The principal division is seen up to the shadows on both sides. The dusky ring is suddenly wider as it crosses the ball. 1880, Oct. 12. 26-inch equatorial.

The seeing is too poor for drawing or measures. To-night the shadow of the ball on the ring on the east side looks very convex to the ball, while on the preceding side it is considerably concave.

1880, Oct. 15. 26-inch equatorial.

(See Figure 12.) Near A and B on the ball are two bright areas. Between them it is darker. Below this dark area it is brighter again. Near the South Pole is a dark olive zone (not so dark as Oct. 11.) The bright knots near A and B are whitish yellow. Just above the equatorial belt the bright space described is less yellow and more inclining to rose-color. The equatorial belt is the brightest part of the ball, and is full of rose-tints. The areas near A and B, and the black shadows just outside them, give to the limb of the ball the straight-line appearance shown in the figure. This phenomenon, which was carefully studied at the telescope, appears to be related to the "square-shouldered" figure of Saturn remarked by W. HERSCHEL, in 1805. The south polar cap helps this effect.

1880, Oct. 18. 26-inch equatorial, eyepiece 400, Wt. 2.

(Drawing omitted.) There is hardly any shadow of the ball on the ring on the west side of the planet, if, indeed, there is any. The shadow of the ball on the east side of the ring appears slightly, though certainly convex to the ball. It is quite narrow. The zone of the ball near the South Pole is dark. The central belt is rosy red.

1880, Nov. 7.

26-inch equatorial, eyepiece 400, Wt. 3.

(See Figure 13.) The shadow of the ring on the ball, Nov. 7, is north of the ring. The distance between the S. edge of this shadow and the principal division in front of the ball is not more than o".3, and yet I see the white line separating them all the time. I even seem to see the principal division here in front of ball better than usual. The dusky ring on the ball is much lighter than the shadow of the ring on the ball. The shadow of ball on ring in the drawing

The shape

is 14 times as wide (east and west) as it should be. is right. Just north of the S. polar dark belt, and at the limb, are two white areas, such as I saw Oct. 15. They produce now something like the square-shouldered aspect, especially on the preceding side, but not so marked as on Oct. 15.

1881, Jan. 12. 26-inch equatorial, eyepieces 400 and 600, observer Professor A. HALL.

(See Figure 14.) "Division of the ring is sharp and clean. Belts on the ball are very faint. Strong moonlight."

1881, July 29. tory, eyepiece 145. 1881, Nov. 27, eyepieces 300, 400. (See Figure 16).

151⁄2-inch equatorial of the Washburn Observa(See Figure 15).

8h 30m Chicago m. t. 151⁄2-inch equatorial, Definition is steady.

Moonlight.

The width of the dusky ring is half of the distance of the ball to the inner edge of Ring B. The shaded part of B is 2/3 of the width of B. There is a notch in the shadow of the ball on the ring, just at the principal division. The division in Ring A at 1/3 of its width from the outer ellipse, is suspected for over an hour. It is plainer at the preceding end; but I am not absolutely sure of it, after all.

1881, Dec. 7. 151⁄2-inch equatorial, powers 260, 430. Sky hazy. (Drawing omitted.) The seeing is very steady, through a light haze. The division in Ring A is suspected, as before (Nov. 27), but it is not perfectly certain. The notched shadow of the ball on the ring is certain. The ends of the shadow of the ring on the north hemisphere of the ball are plainly much wider than the middle of this shadow. Both ends are now equally wide, whereas, on Nov. 27, the east end appeared to be the wider. The markings on the ball appeared in general as they were on Nov. 27, but the whole sky became cloudy before a drawing could be made or measurements begun.

1882, Sept. 25, 15h 30m, Chicago m. t. The seeing is good.

151⁄2-inch equatorial.

(See Figure 17.) On the east side of the planet the outer ellipse of the outer ring prolonged towards the west seems almost exactly tangent to the south limb of the ball. On the west side, on the contrary, the ring seems to be moved upwards (south) so that the principal division (prolonged) is almost tangent to the ball, and the outer ellipse of the ring (prolonged) seems to pass to the south of the ball. The illusion continues even where the principal division alone is regarded.