caused by the ochry tinge of the soil beneath. Clear indications of continents and 

 seas are disclosed by the telescope, the seas presenting a greenish hue. A brilliant 

 white district from time to time is observed in the neighbourhood of his north 

 pole, which decreases in size when it is turned towards the sun. It is highly pro- 

 1 bable that this is the accumulations of snow and ice formed during his long polar 

 winters of twelve months duration, which melt before the sun as the summer 

 season returns. The axis of Mars is inclined to the ecliptic about 30 degrees 18 

 minutes; hence his seasons must be very similar to those of the earth, but of 

 different length ; he has also nearly the same intervals of day and night as we 

 have. 



THE MINOR PLANETS. Next in order of distance, we come to the group of 

 minor planets, or asteroids. They are exclusively telescopic objects, and require 

 very powerful instruments to be discerned. The brightest in the group is Vesta, 

 which appears like a star of the fifth magnitude. The dimensions of these planets, 

 although not accurately ascertained, is comparatively small ; Vesta is computed to 

 be only 250 miles in diameter, and Pallas is supposed to be much smaller. Their 

 orbits are much more eccentric than those of the other planets. 



JUPITER. We now come to the first of a group of planets distinguished for 

 their vast magnitudes, their rapidity of rotation, their comparative lightness, and 

 the enormous extent of their circuits. 



Next to the sun, the planet Jupiter forms the most magnificent body in our 

 system. His great size, being nearly 1,300 times the volume of the earth, the 

 clearness of his light, and his accompaniment of moons, render him a most agree- 

 able object for telescopic observation. The density of Jupiter is little more than 

 that of water, so that the quantity of matter contained in his enormous volume is 

 only equal to about 331 times that of the earth; and it is computed that a liquid 

 on Jupiter, which would be analogous to our oceans, would be three times lighter 

 than sulphuric aether, and would be such that cork would scarcely float on it. The 

 axis of Jupiter being nearly perpendicular to the plane of his orbit, there is no 

 change in the seasons, but perpetual summer at his equator, and winter at the poles. 

 The velocity of his rotary motion is enormous, being at the rate of 28,000 miles 

 an hour. His day is less than ten hours ; but his year is equal to nearly twelve 

 of ours. 



The belts of Jupiter are certain streaks across his disk, running parallel to his 

 equator ; they are not fixed or regular either in size or number, but are observed to 

 vary, to run into each other, and sometimes suddenly to disappear. They are 

 supposed to be clouds floating in the atmosphere of the planet ; or rather, perhaps, 

 the darker body of the planet appearing through the atmosphere. 



The distinguishing feature of the planet Jupiter is his being accompanied by 

 four moons, which revolve round him in periods of time varying from 1 day 18 

 hours, to 16 days. The moons of Jupiter form, with the planet as a central body, 

 a planetary systam in miniature ; the first and fourth are about the siz.e of Mercury; 

 the second and third about the size of our moon. 



SATURN. This planet, the most remarkable body in the system in point of 

 architecture, is nearly twice the distance of Jupiter from the sun ; or, at the mean 

 distance of 900,000,000 miles. 



Saturn rotates upon his axis in 10 hours 29 minutes, forming his day ; and com- 

 pletes his revolution round the sun in 29g of our years, forming one of his. Next 

 to Jupiter, he is by far the largest of the planets, having a diameter of 76,000 

 miles, and a bulk equal to nearly a thousand times that of the earth. The density 

 of Saturn is little more than that of cork. Although never seen by us at a point 

 nearer than 800,000,000 miles, Saturn shines to the naked eye, with a pale, feeble, 

 jet steady light ; but becomes one of the most fascinating objects in the heavens 

 as seen with the telescope. The body of this planet is encompassed with an inner 

 and outer ring, resembling the horizon round a globe, but at a greater comparative 

 distance. The width of the double ring is computed at 30,000 miles ; and the 

 space between the inner ring and the body of the planet 19,000 miles. The figure 

 of Saturn is the flattest of all the planets at the poles, for in addition to the cen- 

 trifugal force generated by his rapid rotation, the attraction of the rings over the 

 equator has aided the accumulation of matter in that region. 



Saturn exhibits belts like Jupiter, indicating an atmosphere ; his seasons, zones, 

 find climates, ure similar to those of the earth, and the tropical and polar pheno- 

 mena are the same. Of his satellites little is known, they require very powerful 

 telescopes to reach them. 



