Feb. 19: 0 h. 40 m.—Two satellites only were in view, west of Jupiter, rather large, and arranged exactly in the same straight line with Jupiter, in the direction of the ecliptic (Fig. 54). The nearer satellite was at a distance of 7´ from Jupiter and of 6´ from the satellite further to the west. Feb. 20.—The sky was cloudy. Feb. 21: 1 h. 30 m.—Three satellites, rather small, were in view, placed thus (Fig. 55). The satellite to the east was 2´ from Jupiter; Jupiter was 3´ from the next, which was on the west; and this one was 7´ from the satellite further to the west. They were exactly in the same straight line parallel to the ecliptic. Feb. 25: 1 h. 30 m. (for on the three previous nights the sky was overcast).—Three satellites appeared, two on the east, which were at a distance of 4´ apart, the same as the distance of the nearer satellite from Jupiter; on the west there was one satellite at a distance of 2´ from Jupiter. They were exactly in the same straight line in the direction of the ecliptic (Fig. 56). Feb. 26: 0 h. 30 m.—A pair of satellites only were present, one on the east, distant 10´ from Jupiter; the other was on the west, at a distance of 6´ (Fig. 57). The eastern satellite was slightly smaller than the western. At the fifth hour three satellites were visible; for, besides the two already noticed, a third satellite was in view, on the west, near Jupiter, very small, which previously had been hidden behind Jupiter, and it was at a distance of 1´ from the planet (Fig. 58). But the satellite on the east was seen to be further off than before, being at a distance of 11´ from Jupiter. On this night, for the first time, I determined to observe the motion of Jupiter and the adjacent planets (his satellites) along the zodiac, by reference to some fixed star; for there was a fixed star in view, eastwards of Jupiter, at a distance of 11´ from the satellite on the east, and a little to the south, in the following manner (Fig. 59). Feb. 27: 1 h. 4 m.—The satellites appeared in the following configuration. The satellite furthest to the east was at a distance of 10´ from Jupiter; the next in order was near Jupiter, being at a distance of 0´ 30´´ from the planet. The next satellite was on the western side, at a distance of 2´ 30´´ from Jupiter; and the satellite further to the west was at a distance of 1´ from this. The two satellites near to Jupiter appeared small, especially the satellite on the east; but the satellites furthest off were very bright, particularly that on the west, and they made a straight line in the direction of the ecliptic exactly. The motion of the planets towards the east was plainly seen by reference to the aforesaid fixed star, for Jupiter and his attendant satellites were nearer to it, as may be seen in the accompanying figure (Fig. 60). At the fifth hour the satellite on the east, near to Jupiter, was 1´ from the planet.