THEY are going-late and early Ever and anon they go, All the wintry time they're passing They are going-only going When with summer earth is dressed, Thick and fast like falling leaves. All along the mighty ages, All adown the solemn time, Little hearts for ever stainless- Seems a sweet "Forget-me-not."-Anon, SIMPLE as a white ray of the sun's light appears, it is found to be made up of three distinct elements, and to have many curious properties. The three elements are light, heat, and force; and they may be separated from each other by means of a prism, which is a solid three-sided piece of glass. The method of doing this is to bore a small hole through the window-shutter of a dark room so as to admit a ray of light from the sun, and then to place the prism level across the hole, with one edge down. When the ray of light passes through the prism it will be bent upward, and strike the wall at a higher point than it did before. It will not, however, be all bent equally in the form of a round spot as at first, but will appear as a long image of seven brilliant and delicate colours, which shade into each other and fade away at the ends of the image. The lowest of the colours, when the prism is placed in the above position, is always red; and the others in order going upward are orange, yellow, green, blue, indigo, violet. When a delicate thermometer is held for a short time in each of the coloured rays it is found that the highest or violet ray gives out least heat, and that the heat grows greater as the thermometer is passed down through the several colours to the red ray. But at a point below the red ray where no light falls there is more heat than anywhere within the light. The rays of light are thus separated from those of heat. Another way of proving that light and heat are distinct elements is this: If a thermometer is placed near a close stove which emits heat but no light, the heat will cause the mercury to rise; but if a plate of glass be placed between the stove and the thermometer the rays of heat cannot pass through the glass, and the mercury will begin to fall, although it is as near the stove as before. If now the stove be made red-hot, the rays of light carry the heat through, and the thermometer again rises, and the nearer the stove comes to a white heat the quicker the dark rays of heat pass through the glass. crystals of rock salt which look quite like glass have not the quality of glass; for the dark rays of heat pass as quickly through them as the rays of light. The It was known hundreds of years ago that the chloride of silver, which is as white as snow, turns black when exposed to the light of the sun; and latterly it has been found that a large number of bodies are thus affected by light. It is this power of light which enables men to take photographs. The force of light can be proved in several ways. It is found to be most powerful in the violet ray, and to reach entirely beyond the light. It cannot be seen by the eye, and does not affect the thermometer. Therefore it is neither light nor heat. Scientific American. "Chloride of silver," a combination of chlorine gas and silver which, spread on the surface of copper plates, formed the first mode of getting sun-pictures. Photographs are now taken on glass thinly coated with collodion which is affected by light in the same way as chloride of silver. Collodion is made by combining gun-cotton with certain acids. QUESTIONS. How many elements are in a ray of light? What are these elements? What is the name of the instruments by which these elements are separated? How is this done? When light passes through a prism placed over the hole in a shutter of a dark room how will it appear? When the prism is so placed which colour is always lowest? Name the other colours in their order going upwards? Which ray gives out least heat? Which gives out most heat? Where is the most heat of all? What rays are thus separated? When a thermometer is placed near a stove which gives out heat but no light what happens? When a plate of glass is placed between the thermometer and the stove what happens? If the stove be made red-hot what happens? XXI.-SUNSHINE AND SHOWER. A-dorn'-ing, beautiful. Blend'-ed, mingled. Bo'd-ing, foretelling. Cloy, become unpleasant. Hei'ght-ened, increased. THE heart that is sinking in sorrow Our life is a state of progression, Hard labour's the price we must pay. Press on; there be regions more charming;-- 50 SUNSHINE AND SHOWER. Then list not yon woe-begone lover, The sooner your pleasures will end. James Ballantine. ERIC, the son of pious and affectionate parents, kept his twelfth birth-day in the early autumn. They had given him many handsome presents, and permitted him to invite a number of his youthful friends to visit him. The children played together in the spacious garden, in a corner of which Eric had a little garden of his own planted with flowers and fruit trees. A few young peach trees stood by the garden wall, bearing their first fruit. They were just beginning to ripen, and their ruddy sides shone already through the down which covered them. The tempting sight excited the longing appetite of the boys. But Eric's father had forbidden him to touch those trees, and he did not wish to disobey his father's command. But the other boys were eager to taste the fruit, and at last |