carried a printed bill upon its face. This rapidly revolving placard was illuminated for a moment by a flash from a Leyden jar. When the prepared plate was examined by means of a developing agent, it was found, that notwithstanding the rapidity with which the image moved over the lens and the transient nature of the light—a picture of the printed bill was clearly formed, with the letters perfect. This was an experiment of Mr Fox Talbot's, and is perhaps the most remarkable of the many examples of natural magic with which photography has brought us acquainted.

It has long been a problem, the solution of which has been anxiously looked for, whether we might hope to obtain pictures in all the beauty of natural colour. This had not yet been quite successfully accomplished; but the approaches towards it are so favourable that we may hope, in a few years, to find our photographic pictures coloured by the agent which now draws them.

That the delicate and fading images of the camera obscura should be permanently secured upon plates of metal and glass, and on paper, was, at one time, beyond the dreams of science. We rejoice in the reality, and Nature herself paints for us the portrait of a friend, or those scenes which are endeared to us by the tenderest and most refined associations.

We have now the means of obtaining the most truthful representations of the pyramids and the tombs of Egypt. The Assyrian Excavation Society have realisations from the pencil of the sunbeam of all that remains of the great monarchies of the East. The traveller in Central America has secured, with his camera, pictures of the wonderful

works of the Aztecs and the contemporary races, of whom we know so little, but whose works remain to speak of a savage grandeur and an advanced state of art, rivalling that which we find in the palace of Sardanapalus and the temples of the early Pharaohs. The ethnologist rejoices in his collection of portraits from all parts of the world; in his quiet home he is enabled, by the aid of photography, to study the physiognomies of all the races on the face of the earth.

The natural philosopher uses the same art to register for him the variations of atmospheric pressure and of the earth's temperature; more than this, the alterations in the magnetic intensity of this terrestrial globe are now faithfully registered by photography. The microscopist makes the light draw for him the details of organisation, which it would be impossible for the human hand to trace. The astronomer places a sensitive tablet in his telescope; and not only does the sun draw his own image, but the milder moon traces out for him her mountains and her valleys, her beetling precipices, like old sea-coasts, and her dreadful volcanic craters, large and deep enough to swallow up all England.

What, then, may we not expect from photography, with the advance of science?

A few years since it was thought that two or three salts of silver and of gold were the only bodies which underwent any remarkable change when exposed to the action of the solar rays.

It is now proved that it is not possible to expose any body, whatsoever may be its character, to the action of sun shine without its undergoing a chemical or a mechanical

change. For example, take a plate of glass, of metal, of stone, or a surface of leather, or resin-in fact, any organic or inorganic body, and, placing a perforated screen above it, expose it for a short time to solar influence; then treating the plate as we do the Daguerreotype,-exposing it to the vapour of mercury,- —we shall find a picture of the superposed screen most faithfully made out on the surface; proving thus that it is impossible to expose any substance to sunshine without its undergoing a change; and that constant sunshine would be destructive to the permanence of matter, as now constituted. It has, however, ben found that Nature has a beautiful provision for restoring the deranged conditions. During darkness, by the action of some peculiar molecular forces, all bodies possess the power of restoring themselves to the state in which they were previously to the destructive action of the sunshine; and as night and repose are required to restore to the animal and vegetable economy the vital forces which have become exhausted by the labours of the day, and the excitements which depend upon light, so are night and darkness required to ensure the permanence of the inorganic masses of the earth's surface.

Can there be a more beautiful provision than this? The laws by which the Eternal Creator works are indeed wonderful and grand; the study of creation's mysteries induces a refinement of the mind, and a holy tranquillity of spirit. No one can arise from reading a page of Nature's mighty volume without feeling himself to be

"A wiser and a better man."

R. H.*

* In "Excelsior," 1855.

PORTRAITS IN OUTLINE.

L-CHRISTIAN FREDERICK SWARTZ.

"THE glory of God is an object worth living for:" so thought a godly woman, as she lay on her deathbed, and busy memory was leading her thoughts back over the years she had lived, and forward to the eternity on which she was soon to enter. The shades of evening were creeping over the earth, the sighing of the wind among the trees seemed to speak of sorrow, and, in the fall of the brown leaves of autumn might be heard the words, "We all do fade as a leaf." Dim and dreary looked all outward things; but in that chamber of the dying there was light, and hope, and joy. The soul had, long before, made its peace with God, through the blood of Jesus; and now, when crossing the dark waters, it lay back in His arms, and was held gently and sweetly, waiting till the light appeared on the other side. But the mother's heart was still there, and it was working; and its work was prayer. There were the little children, whom she knew Jesus loved. Lord, thou hast taken me and washed me from my sins-wilt thou not take those little ones, whom thou hast given me? This one, Lord, my first-born son— I give him to thee; use him in thy service-let him be a little Samuel." It is this little boy, thus dedicated to God by his godly mother, whose life and work we wish to trace. You may have heard of him, for the name of the righteous is held in everlasting remembrance. He is known as Christian Frederic Swartz.

His mother died and was buried, but no immediate result seemed to follow the dedication and the prayers. Yet he was a hopeful child; and his father resolved he should be well furnished with weapons of warfare in a Christian education. Time would shew if he could use them. He was, therefore, kept busy and diligent in a grammar school at Halle.

It is sweet to think of this young German lad, as he wended his way from his home to this school, while the light breezes fanned his manly cheek, and played among his dark locks, his thoughts being busy, busy with the future, as he wondered what God would have in store for him. Might not a tree, a shrub, a flower, a sound of music, or the old familiar road, recall his mother's last wish concerning him-and while his eyes might seem fixed on some passing object, they might only see in vision that dear wasted form, and feel those hot, shadowy fingers, as they lay on his head, as she gave him up to God-or his whole soul might go out in prayer, that God would accept that offering, and make him His servant? To be of use in the work of God, that work must begin in the man's own soul; and love to God must grow so strong that it cannot be restrained from telling to others what a Saviour Jesus is, and how willing he is to save sinners, even the chief. The more love, the greater the wish to tell of the love of Jesus, even where Satan has his seat. In the year 1742, a pale-faced, worn-out man came and took up his abode in Halle. "What is your new neighbour's name ?" would ask one "Schultz!" was the answer; "and though he is so ill, he will not rest, but writes on continually, and they say he

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woman of another.