A cry from the mountain's summit- Bearing his precious prey! She cannot mark his flight; By their shouts again they rouse him, He wheels away on the mountains brow- Crag after crag she is gaining, She pauses not for breath; What sound has met her ears? PART II. In her kirtle's ample foldings, She sees the trackless steep; She looks in mute despair; All hearts to pray for her, The goat's light foot-marks tracing, She stepp'd where human foot ne'er trod, At times, o'erwhelmed and weary, Young Donald was his mother's stay, To this Authoress we are indebted for one of the most delightful pieces of fairy fiction in our language, which, as it has not yet been sufficiently noticed by reviewers, we will conclude the present paper by analysing. The work to which we allude, is entitled PHANTASMION.* The story thus opens : "A young boy hid himself from his nurse in sport, and strayed all alone in the garden of his father, a rich and mighty prince. He followed the bees from flower to flower, and wandered farther than he had ever gone before, till he came to the hollow tree where they hived, and watched them entering their storehouse, laden with the treasures they had collected. He lay upon the turf, laughing and talking to himself; and, after a while, he plucked a long stiff blade of grass, and was about to thrust it in at the entrance of the hive, when a voice, just audible above the murmur of the bees, cried, 'Phantasmion!' Now the child thought that his nurse was calling him in strange tones; and he started, saying, "Ah! Leeliba!" and looked around; but casting up his eyes, he saw that there stood before him an ancient woman, slenderer in figure than his nurse, yet more firm and upright, and with a countenance which made him afraid. 'What dost thou here, Phantasmion?' said the stranger to the little boy; and he made no answer. Then she looked sweetly * London, William Pickering, 1837. upon the child, for he was most beautiful; and she said to him, 'Whom dost thou take me for?' And he replied, At first I took thee for my nurse, but now I see plainly that thou art not like her.' And how am I different from thy nurse?" said the strange woman. The boy was about to answer, but he stopped short, and blushed; then after a pause, he said, 'One thing is, that thou hast wings upon thy shoulders, and she has none.'" It is the faery, Potentilla, who, finding the boy frank and generous, is determined to repay him. Taking from him a pomegranate, which he had procured for her with peril— "the only ripe one which grew on a tree hard-by"-she looked kindly on Phantasmion, and said, "My little Phantasmion, thou needest no faery now to work wonders for thee, being yet so young, that all thou beholdest is new and marvellous in thine eyes. But the day must come when this happiness will fade away; when the stream, less clear than at its outset, will no longer return such bright reflections: then, if thou wilt repair to this pomegranate tree, and call upon the name of Potentilla, I will appear before thee, and exert all my power to renew the delights and wonders of thy childhood." Clear enough it is that they are the gifts of genius which the faëry had promised to the boy-genius, which is the permanence of youth to the individual. Well; Phantasmion's fair mother, the Queen Zalia, fell sick and died. When told by one of the royal gardeners that his mother is dead, How darest thou,' cried the boy in a haughty tone, · say that my mother is dead? Go to her chamber, and see,' replied the man sternly. And how can I see her if she is dead?' rejoined the boy, with a tremulous laugh. Can I see the cloud of yesterday in yon clear sky? Like the clouds, the dead vanish away, and we see them no more!" What can be more Coleridgean in tone and feeling than this. His father, Dorimant, dying of poisoned honey, Phantasmion inherits, all too young, the throne of Palmland. He finds, however, a friend in one Dariel of Tigridia; but he soon dying of a scorpion's bite, the young prince grows melancholy. Are not all persons and things connected with himself doomed to misfortune? Phantasmion had spent many days in a state of dejection, when he wandered forth, after a sleepless night, one clear morning, and refreshed by the breath of early dawn, began to slumber under the boughs of a pomegranate tree. Here he meets again the faery Potentilla. At the waving of her wand the air is filled with butterflies, that Phantasmion may select from among them a pair of wings for his own shoulders. The moment that Potentilla touched him with her wand, a sensation of lightness ran throughout his body, and instantly afterwards he perceived that wings played on his shoulders, wings of golden green, adorned with black embroidery. Beneath an emerald coronet his radiant locks clustered in large soft rings, and wreathed themselves around his snowy forehead. Robes of white silk floated over his buoyant limbs, and his full eyes, lately closed in languor, beamed with joyful expectation, while more than childlike bloom rose mantling to his cheek. Potentilla had seen an eagle teaching her young ones to fly, gradually widening her airy circles, and mounting in a spiral line, that swelled as it rose, while the sun burnished her golden plumes; just so she flew before the winged youth, who timidly followed where she led the way, trembling in his first career when he saw the earth beneath him. But, gaining confidence, all at once he shot away from his guide, like a spark from a sky-rocket. He soared, and gyred, and darted on high, describing as many different figures as a skater on the ice, while from the groves and flowery meads below this choral strain resounded, See the bright stranger! Eagles that high on the crest of the mountain, Beyond where the cataracts gush from their fountain, Look out o'er the sea and her glistering shores, wards, Phantasmion acquires power to leap like a grasshopper, and by this means progresses from kingdom to kingdom. At another, he takes the shape of a sea-beetle, and other insects, until at length he succeeds in winning the lady of his love, defeating his foes, and securing his throne. Verily, the soul of Coleridge has passed into his daughter! Her Phantasmion is honey-full of the most beelike fantasies-richer than Hyblagenial-musical-and dewy-footed. Why has not this book, long ere this time, reached a second-a fifth edition? CENSUS OF SCIENTIFIC THEORIES. 1 No. 4-THE UNDULATORY THEORY OF LIGHT. BY CHARLES TOOGOOD DOWNING, M.R.C.S.-Author of the "Fanqui in China,” &c. (Concluded from page 569). It is generally believed that the phenomena of double refraction and the polarisation of light, will scarcely admit of a popular explanation; and on this account, the subject has been almost entirely neglected by general readers. The mathematical formulæ with which the results of the minute and delicate experiments have been expressed by the learned and scientific, are certainly enough to create a distaste at first for their investigation, but we venture to assert that upon attentive examination, a more pleasing and astonishing branch of enquiry cannot be pointed out. To those who have studied the ordinary phenomena of light and colours, and derived pleasure from experimenting with optical instruments, it may be sufficient merely to suggest, that the study of double refraction and polarisation will introduce him to a new world, and enable him to scrutinize, with a new and wonderful agent, the most minute and secret mysteries of nature. The finest and most brilliant exhibitions may be made by the experimentalist, and if the study be prosecuted with zeal and industry, there is scarcely a doubt but that new and wonderful facts may be discovered. In our opinion it is quite possible that the wonders of this new science might be rendered perfectly intelligible to those readers, who possess but a very slender portion of either mathematical or physical knowledge. It would afford us great pleasure if that were our task, but the limits which are necessarily assigned us for the explanation of the subject of these papers, will prevent any other than a cursory notice of those points which bear upon the undulatory theory. The first origin and order of succession of the discoveries, will probably form the most interesting plan of proceeding, and we therefore commence with double refraction. The meaning of this term may be thus briefly explained; If a ray of N. S.-VOL. I. 4 T solar or other light is made to pass through a piece of glass, or vessel of water, it will have the same appearance, and be possessed of the same properties after transmission as before it. Any object seen through them will appear single, and therefore we say that the glass and water refract singly. But if a similar ray of light is made to pass through a crystal of Iceland spar, it will not emerge singly as before, but will be divided in passing through the transparent substance into two rays, and any object seen through this crystal will appear double. Any body therefore, which like the Iceland spar separates the beam of light into two separate portions, is said to be a doubly refracting crystal, and the ray so split or divided, is said to be doubly refracted. It will be discovered upon investigation, that one of these refracted rays, is refracted according to the ordinary law of refraction, and it is hence called the ordinary pencil; while the other is called the extraordinary pencil, from its being refracted according to a law different from the ordinary law. This curious property of some transparent bodies, was discovered by a physician of Copenhagen, of the name of Erasmus Bartholinus, about the middle of the seventeenth century. He procured from one of the Danish merchants who traded to Iceland, a specimen of crystal, and immediately made a number of chemical and optical experiments upon it. He published an account of these at Copenhagen, in 1669, and thus directed the attention of the scientific to the subject. His notion of the cause of double refraction was, that he supposed the Iceland crystal to have two sets of pores; one "according to the ductus, or direction of the sides, and parallel thereto : since it may be observed, that according to this disposition of the sides it is broken, and the parts severed from one another; and that one of the images, namely the movable, passeth through them. Next besides these pores lying according to the parallelism of the sides, it hath others, such as glass, water, and right crystals have, through which the right image is transmitted." It is unnecessary to follow Bartholinus through the whole of his experiments, especially as the results were comparatively trifling. These facts appear to have been discovered by him. 1 That Iceland spar has the property of double refraction. 2. That one of these refractions is performed according to a law which is common to all transparent solids and fluids, while the other is performed according to an extraordinary law, which had not previously been observed by philosophers; and 3. That the incident light is equally divided between the ordinary and extraordinary pencils. The celebrated Christopher Huygens was at first afraid that these facts discovered by Bartholinus, would militate against the theory of undulations which he was promulgating. He directed his attention therefore to the subject; in order both to obviate any objections which might be urged against his particular views, and to reconcile, if possible, the two classes of phenomena. His researches appeared in the fifth chapter of his Traité de la Lumière to which we have already alluded. By a series of ingenious and well-executed experiments, he arrived at the fact, that when the ray of light is incident along the axis of the crystal, there is little or no separation into the ordinary and extraordinary beams. This axis is the principal section of the crystal, and may be 1 also considered the axis of double refraction. The Iceland spar being of the form of a rhomb, and its principal section the bisection of one of its obtuse angles, every object seen through it in that direction, will be single. In every other position, the refraction is double, and the greater or less divergence of the beams, depends upon a law discovered by Huygens, and which is considered very accurate. The double refraction increases in proportion as the inclination of the ray to the axis increases, so that it is at its minimum at the pole, and its maximum at the equator. When Huygens wished to determine the law of the two refractions, he drew a black line A B fig. 3. upon a smooth surface, and two other lines CE D and K M L perpendicular to it, and having their distance Fig. 3. greater or less according to the obliquity at which the refraction was to be examined. Now by placing the doubly refracting crystal upon E, that A B is parallel to the principal section or axis E G, and placing the eye above it, the line A B was seen single, but the line C D was double.* This experiment is very simple and may be easily performed, and in order to distinguish the ordinary from the extraordinary image, it will be observed that the latter always appears more elevated than the former; or if you turn the crystal round, it will be observed that the ordinary image appears fixed, while the extraordinary one revolves round the other. If the eye be now placed at I, perpendicular to A B, till it sees the ordinary image of CD coinciding with the part of CD without the crystal, let the point H be marked on the crystal, where the intersection at E appears. Let the eye be now taken towards O, in the same perpendicular plane till the ordinary image of CD coincides with K L, and let the point N where the intersection E now appears, be marked upon the crystal. The lines N H, E M and H E the thickness of the crystal being accurately measured, then joining N E and N M the ratio of re Edin. Phil. Journal, vol. ii. |