The intensity of the sun’s light diminishes from the centre to the circumference of the solar disc. His direct light has been estimated to be equal to that of 5563 wax candles of moderate size placed at the distance of one foot from an object; that of the moon is probably only equal to the light of one candle at the distance of 12 feet: consequently the light of the sun is more than three hundred thousand times greater than that of the moon. According to Professor Secchi’s experiments at Rome, the heat of the solar image is almost twice as great at the centre as at the edge. The maximum heat, however, is not in the centre, but in the solar equator, and the spots are less hot than the rest of the surface. The oceans of light and heat probably arising from electric or chemical processes of immense energy that continually take place at the sun’s surface (N. 217) are transmitted in undulations by the ethereal medium in all directions; but notwithstanding the sun’s magnitude and the inconceivable intensity of light and heat that must exist at his surface, as the intensity of both diminishes as the square of the distance increases, his kindly influence can hardly be felt at the boundaries of our system. In Uranus the sun must be seen like a small brilliant star not above the hundred and fiftieth part as bright as he appears to us, but that is 2000 times brighter than our moon, so that he is really a sun to Uranus, and may impart some degree of warmth. But if we consider that water would not remain fluid in any part of Mars, even at his equator, and that, in the temperate zones of the same planet, even alcohol and quicksilver would freeze, we may form some idea of the cold that must reign in Uranus and Neptune. The climate of Venus more nearly resembles that of the earth, though, excepting at her poles, much too hot for animal and vegetable life such as they exist here, for she receives seven times as much light and heat as the earth does; but in Mercury the mean heat from the intensity of the sun’s rays must be above that of boiling quicksilver, and water would boil even at his poles. Thus the planets, though kindred with the earth in motion and form, are, according to our experience, totally unfit for the habitation of such a being as man, unless indeed their temperature should be modified by circumstances of which we are not aware, and which may increase or diminish the sensible heat so as to render them habitable. In our utter ignorance it may be observed, that the earth, if visible at all from Neptune, can only be a minute telescopic object; that from the nearest fixed star the sun must dwindle to a mere point of light; that the whole solar system would there be hid by a spider’s thread; and that the starry firmament itself is only the first series of starry systems, the numbers of which are bounded alone by the imperfection of our space-penetrating instruments. In this overwhelming majesty of creation,