a number of barons entered. My lord,' said the Earl of Leicester to the archbishop, the king requires you to come to his presence and answer to certain things which will then be alleged against you, as you promised yesterday to do.' My lord earl,' said Becket,' thou knowest how long and loyally I served the king in his worldly affairs. For that cause it pleased him to promote me to the office which now I hold. I did not desire this office; I knew my infirmities. When I consented it was for the sake of the king alone. When I was elected I was formally acquitted of my responsibilities for all that I had done as chancellor. Therefore I am not bound to answer, and I will not answer.'

The earls carried back the reply. The peers by a swift vote declared that the archbishop must be arrested and placed under guard.

The earls re-entered, and Leicester approached him and began slowly and reluctantly to announce the sentence. 'Nay,' said Becket, lifting his tall meagre figure to its haughtiest height, 'do thou first listen to me. The child may not judge his father. The king may not judge me, nor may you judge me. I will be judged under God by the pope alone, to whom in your presence I appeal. I forbid you under anathema to pronounce your sentence. And you, my brethren,' he said, turning to the bishops, since you will obey man rather than God, I call you too before the same judgment-seat. Under the protection of the Apostolic See, I depart hence.'

No hand was raised to stop him. He swept through the chamber and flung open the door of the hall. He stumbled on the threshold, and had almost fallen, but recovered himself. The October evening was growing into twilight. The hall was thronged with the retinues of the king and the barons. Dinner was over. The floor was littered with rushes and fragments of rolls and broken meat. Draughts of ale had not been wanting, and young knights, pages, and retainers were either lounging on the benches or talking in eager and excited groups. As Becket appeared among them, fierce voices were heard crying' Traitor! traitor! Stop the traitor! Among the loudest were Count Hamelin, the king's illegitimate brother, and Sir Ranulf de

Broc, one of the Canterbury knights. Like a bold animal at bay, Becket turned sharply on these two. He called Count Hamelin a bastard boy. He reminded De Broc of some near kinsman of his who had been hanged. The cries rose into a roar; sticks and knots of straw were flung at him. Another rash word, and he might have been torn in pieces. Some high official hearing the noise came in and conducted him safely to the door.

In the quadrangle he found his servants waiting with his palfrey. The great gate was locked, but the key was hanging on the wall; one of them took it and opened the gate, the porters looking on, but not interfering. Once outside he was received with a cheer of delight from the crowd, and with a mob of people about him he made his way back to the monastery. The king had not intended to arrest him, but he could not know it, and he was undoubtedly in danger from one or other of the angry men with whom the town was crowded. He prepared for immediate flight. A bed was made for him in the chapel behind the altar. After a hasty supper with a party of beggars whom he had introduced into the house, he lay down for a few hours of rest. At two in the morning, in a storm of wind and rain, he stole away disguised with two of the brethren. He reached Lincoln soon after daybreak, and from Lincoln, going by cross paths, and slipping from hiding-place to hiding-place, he made his way in a fortnight to a farm of his own at Eastry, near Sandwich. He was not pursued. It was no sooner known that he was gone from Northampton than a proclamation was sent through the country forbidding every man under pain of death to meddle with him. The king had determined to allow the appeal, and once more to place the whole question in the pope's hands. The Earl of Arundel with a dozen peers and bishops was despatched at once to Sens to explain what had happened, and to request Alexander to send legates to England to investigate the quarrel and to end it. The archbishop, could he have consented to be quiet, might have remained unmolested at Canterbury till the result could be ascertained. But he knew too well the forces which would be at work in the papal court to wait for its verdict. His confidence was only in himself. Could

he see the pope in person, he thought that he could influence him. He was sure of the friendship of Lewis of France, who was meditating a fresh quarrel with Henry, and would welcome his support. His own spiritual weapons would be as effective across the Channel as if used in England, while he would himself be in personal security. One dark night he went down with his two companions into Sandwich, and in an open boat crossed safely to Gravelines. At St. Omer he fell in with his old friend Chief Justice de Luci, who was returning from a mission to the court of France. De Luci urged him to return to England and wait for the pope's decision, warning him of the consequences of persisting in a course

which was really treasonable, and undertaking that the king would forgive him if he would go back at once. Entreaties and warnings were alike thrown away. He remained and despatched a letter to the pope saying briefly that he had followed the example of his holiness in resisting the encroachments of princes; and had fled from his country. He had been called to answer before the king as if he had been a mere layman. The bishops, who ought to have stood by him, had behaved like cowards. If he was not sustained by his holiness, the Church would be ruined, and he would himself be doubly confounded.-The Nineteenth Century..

WHEN we see the brilliant colors reflected by the glass lustres and chandeliers which are now so commonly used for decorative purposes, we seldom bestow a thought upon them, regarding them as things too common, perhaps too trivial to be worthy of any particular attention. We are content to know that a triangular piece of glass will exhibit certain bright colors-they look very pretty, and it does not matter much how they happen to be there. This is the common way of dealing with the natural phenomena which meet us at every turn in this wonderful world in which we live. The progress of civilisation, with all its triumphs of Science and Art, would indeed have been slow, if not altogether at a dead-lock, if every one had been content to treat such matters in this summary fashion. But happily, this has not been the case, for certain intellectual giants have from time to time arisen, who have grappled with these things, and have devoted their lives to their investigation.

Such a one was Sir Isaac Newton, who just about two centuries ago, with rough appliances fashioned by his own hands, inquired into the meaning of the colors to which we have just aliuded. We cannot do better than quote his own words, from a letter which he addressed to the Royal Society in 1672; for his statement is so clear that a child can easily understand what he means. 'I procured me a triangular glass prisme,' writes he, 'to try therewith the celebrated phenomena of colors. And in order thereto having darkened my chamber and made a small hole in my window-shuts to let in a convenient quantity of the sun's light, I placed my prisme at his entrance, that it might be thereby refracted to the opposite wall.'

He goes on to say how surprised he

was to find that the ray of light, after passing through the prism, instead of being thrown upon the wall in the form of a round spot, was spread out into a beautiful colored ribbon; this ribbon being red at one end, and passing through orange yellow green and blue, to violet at its other extremity. Upon this experiment is founded the theory of color, which with few modifications, still remains unquestioned.

It was not until the beginning of the present century that this experiment of Newton's (repeated as it had doubtless been in the meantime by many philosophers) was found by Dr. Wollaston to possess certain peculiarities which defied all explanation. He found that, by substituting a slit in the shutter of the darkened room for the round hole which Newton had used, the ribbon of color, or spectrum as it is now called, was intersected by certain dark lines. This announcement, although at the time it did not excite much attention, led to further experiments by different investigators, who, however, vainly endeavored to solve the meaning of these bands of darkness. It was first observed by an optician of Munich that they never varied, but always occupied a certain fixed position in the spectrum; moreover he succeeded in mapping them to the number of nearly six hundred, for which reason they have been identified with his name, as 'Fraunhofer's lines.'

In 1830, when improved apparatus came into use, it was found that the number of these lines could be reckoned by thousands rather than hundreds; but their meaning still remained a puzzle to all. By this time Newton's darkened room with the hole in the 'windowshuts' had been, as we have just said, greatly improved upon. The prism was now placed in a tube, at one end of

which was a slit to admit the light, while the retina of the observer's eye received the impression of the spectrum at the other end. This is the simplest form of the instrument now known as the spectroscope, and which is, as we have shewn, a copy in miniature of Newton's arrangement for the decomposition of white light into its constituent colors.

We must now go back a few years to record some experiments carried out by Herschel, which, quite independent of the spectroscope, helped others to solve the problem connected with the dark lines. He pointed out that metals, when rendered incandescent under the flame of the blow-pipe, exhibited various tints. He further suggested that as the color thus shewn was distinctive for each metal, it might be possible by these means to work out a new system of analysis. A familiar instance of this property in certain metals may be seen in the red and green fire which is burned so lavishly during the pantomime season at our theatres; the red owing its color to a preparation of the metal strontium, and the green in like manner to barium. Pyrotechnists also depend for their tints not only upon the two metals just named, but also upon sodium, antimony, copper, potassium, and magnesium. Wheatstone also noticed the same phenomena when he subjected metals to the intense heat of the electric current; but it was reserved for others to examine these colors by means of the spectroscope. This was done by Bunsen and Kirchhoff in 1860, who by their researches in this direction, laid the foundation of a totally new branch of science. They discovered that each metal when in an incandescent state exhibited through the prism certain distinctive brilliant lines. They also found that these brilliant lines were identical in position with many of Fraunhofer's dark lines; or to put it more clearly, each bright line given by a burning metal found its exact counterpart in a dark line on the solar spectrum. It thus became evident that there was some subtle connection between these brilliant lines and the dark bands which had puzzled observers for so many years. Having this clue, experiments were pushed on with renewed vigor, until by some happy chance, the vapors of the burning metals were examined through the agency of NEW SERIES.-VOL. XXVI., No. 3

the electric light. That is to say, the light from the electric lamp was permitted to shine through the vapor of the burning metal under examination, forming, so to speak, a background for the expected lines. It was now seen that what before were bright bands on a dark ground, were now dark bands on a bright. ground. This discovery of the reversal of the lines peculiar to a burning metal,. when such metal was examined in the form of vapor, led to the enunciation of the great principle, that vapors of metals at a lower temperature absorb exactly those rays which they emit at a higher.'

To make this important fact more clear, we will suppose that upon the redhot cinders in an ordinary fire-grate is thrown a handful of saltpetre. (This. salt is, as many of our readers will know, a chemical combination of the metal potassium with nitric acid-hence called' nitrate of potash, or more commonly nitre.) On looking through the spectroscope at the dazzling molten mass thus produced, we should find that (instead of the colored ribbon which the sunlight. gives) all was black, with the exception. of a brilliant violet line at the one end of the spectrum, and an equally brilliant red line at the other end. This is the spectrum peculiar to potassium; so that,. had we not been previously cognisant of the presence of that metal, and had been requested to name the source of the flame produced, the spectroscope would have enabled us to do so without difficulty.. We will now suppose that we again examine this burning saltpetre under altered conditions. We will place the red-hot. cinders in a shovel, and remove them to the open air, throwing upon them a fresh supply of the nitre. We can now examine its vapor, whilst the sunlight forms a background to it; when we shall see that. the two bright colored lines have given place to dark ones. This experiment. will prove the truth of Kirchhoff's law so far as potassium is concerned, for the molten mass first gave us the bright lines, and afterwards by examining the cooler vapor we saw that they were transformed to bands of darkness; in other words they were absorbed. (In describing the foregoing experiment, we have purposely chosen a well-known substance, such as saltpetre, for illustration; but in prac

20

tice, for reasons of a technical nature, a different form of potassium would be employed.) Kirchhoff's discovery forms by far the most important incident in the history of the spectroscope, for upon it are based the new sciences of Solar and Stellar Chemistry, to which we will now direct our readers' attention.

The examination of the heavenly bodies by means of the spectroscope has not only corroborated in a very marvellous manner the discoveries of various astronomers, but it has also been instrumental in correcting certain theories and giving rise to new ones. The existence of a feebly luminous envelope extending for hundreds of thousands of miles beyond the actual surface of the sun, has been made evident whenever an eclipse has shut off the greater light, and so permitted it to be viewed. The prism has shewn this envelope, or chromosphere as it called, to consist of a vast sea of hydrogen gas, into which enormous flames of magnesium are occasionally injected with great force. (We need hardly remark that these facts are arrived at analogously by identifying the absorption lines with those given by the same elements when prepared artificially in the laboratory.) This chromosphere can, by the peculiar lines which it exhibits in the spectroscope, be made manifest when ever the sun itself is shining.

The foregoing discovery has given astronomers the advantage during a transit of Venus—of viewing the position of the planet both before and after its passage across the sun's disc; for it is evident that the presence of an opaque body in front of the chromosphere will cut off the spectral lines in the path which it follows; so that although the planet is invisible its exact place can be noted. From a comparison of these lines with those that can be produced in the laboratory, it is rendered probable that no less than thirteen different metals are in active combustion in the body of the sun. From certain geological appearances, it is conjectured that our own earth was once in this state of igneous fusion, and although our atmosphere is now reduced to a few simple elements, it must once have possessed a composition as varied as that of the sun. As it is, the air which we breathe gives certain spectral lines. These are much increased in number

when the sun is low, and when therefore it is viewed through a thicker medium. In this case the blue and green rays are quickly absorbed, while the red pass without difficulty through the denser mass of air, thus giving the setting sun his blood-red color. It will now be readily understood how, by means of the spectroscope, the existence of atmosphere in the superior planets can be verified. What a world of conjecture is thus opened out to us! for the existence of atmosphere in the planets argues that there are seas, lakes, and rivers there subject to the same laws of evaporation as those upon our own earth. And if this is so, what kind of beings are they who inhabit these worlds?

The moon shews no trace of atmosphere, so that we may assume that if there be living beings there, they must exist without air and without water. The lines given by the moon and planets being in number and position identical with those belonging to the solar spectrum, is a further proof, if any were needed, that their light is borrowed from the sun.

The varied colors of the fixed stars may be assumed to be due (from what we have already stated with regard to metallic combustion) to their chemical composition; and the spectroscope, by the distinctive lines which it registers, renders this still more certain. Their distance from us is so vast, so immeasurably beyond any conception of space that we can command, that the detection of their composition is indeed a triumph of scientific knowledge. It has been calculated that if a model of the universe were made in which our earth were depicted as the size of a pea, the earth itself would not be one-fifth large enough to contain that universe.

If we marvel at the extraordinary skill which has brought these distant spheres under command of an analytical instrument, we must wonder still more when we are told that the spectra of these bodies can be brought within range of the photographic camera. This has lately been done by the aid of the most complicated and delicate mechanism; the difficulty of keeping the image stationary on the sensitive collodion film during the apparent motion of the stars from east to west, having only just been surmounted. This power of photograph