in Astronomy, one of the eleven planets, situated without the earth's orbit, and remarkable for the extent of its atmosphere and the redness of its light. See ASTRONOMY Index.

The red colour of this planet, according to Mr Brewster*, is owing to the same cause as the redness of the morning and evening clouds. When a beam of white light passes through any medium, its colour in- *Supplementary Chapters to Ferguson's Astronomy, clines vol. ii. clines to red, in proportion to the space through which it has travelled, and the density of the medium. The momentum of the red or least refrangible rays being greater than that of the violet or most refrangible rays, the former will make their way through the resisting medium, while the latter are either reflected or absorbed. The colour of the beam, therefore, when it reaches the eye, must partake of the colour of the least refrangible ray; and the redness of this colour must increase with the number of the violet rays that have been obstructed. Hence we see, that the sun, moon, and stars appear red when in the horizon; and that every luminous object seen through a mist is of a ruddy hue. Now, the planet Mars is allowed to have an atmosphere of great density and extent, as is manifest from the dim appearance of the fixed stars that are placed at a considerable distance from his disk. The sun's light, therefore, by which this planet is illuminated, having to pass twice through the atmosphere of Mars before it reaches the earth, must be deprived of a great proportion of the violet rays; and consequently the colour of the resulting light by which Mars is visible, must be red.—As there is a considerable difference of colour among the other planets, and likewise among the fixed stars, are we not entitled to conclude, that those in which the red colour predominates, have the greatest or the densest atmospheres? According to this principle, Saturn must have the next greatest atmosphere to that of Mars.

in Pagan worship, the god of war. He was, according to some, the son of Jupiter and Juno; while others say that he was the son of Juno alone, who being displeased at Jupiter's having produced Minerva from his brain, without female aid, in revenge conceived without the affluence of the other sex, by touching a flower shown to her by Flora in the plains of Olens, and became the mother of this formidable deity. The amours of Mars and Venus, and the manner in which Vulcan caught and exposed them to the laughter of the other gods, have been described by several of the ancient poets. He is represented as having several wives and mistresses, and a considerable number of children. He was held in the highest veneration by the Romans, both from his being the father of Romulus their founder, and from their inclination to conquest; and had magnificent temples erected to him at Rome.

Mars is usually represented in a chariot, drawn by furious horses. He is completely armed; and extends his spear with the one hand, and grasps a sword, imbrued in blood, with the other. He has a fierce and savage aspect. Discord is represented preceding his car; and Clamour, Fear, and Terror, appear in his train. The victims sacrificed to him were the wolf, the horse, the woodpecker, the vulture, and the cock.

among the older chemists, denotes iron; that metal being supposed to be under the influence of the planet Mars.