a a, the upper and larger pair of electric organs.

bb, the lower pair. cc, two muscles dividing the upper from the lower pair of electric organs. d d dd, four external lateral muscles. e, a single muscle inserted into the fin f. 7g, eight dorsal muscles, imbedded in fat and cellular tissue, and having a concentrically-laminated structure. h, the spinal column. i, the swimming bladder, which is of an elongated form and of great length,

measuring from two to nearly three feet.

WITH powers so formidable, we cannot wonder that these animals, in the countries where they abound, are dreaded by the natives; and this dread, among other things, is one of the causes why the instances are so few, in which living specimens have been brought to Europe; it deters the natives from attempting to procure them. At the present moment, one of these animals exists in the Gallery of Practical Science, Adelaide street, London, where it is in good health, and full of energy. Mr. Bradley, the director, writing to the Magazine of Natural Science, (November, 1839,) says, "When we first began to experiment on the electrical powers of this animal, we could only produce those phenomena which depend on the tension of the electricity as the spark, etc., by employing secondary currents; now, on the contrary, we have discarded Henry's coil from our apparatus, and invariably succeed, not only in obtaining

a direct spark, but even the deflagration of gold leaves, these leaves being mutually attracted from a sensible distance, and burning on coming into contact."

The ancients, who were well acquainted with the torpedo, though they knew nothing of electricity in itself, were accustomed to avail themselves of that animal in effecting the cure of certain maladies. Scribonius Largus says, "Pain in the head, however inveterate and severe, is immediately taken away, and effectually cured, by the application of the black torpedo alive to the affected part, which must be retained there until the pain ceases, and a sense of numbness succeeds; the remedy must then be removed, lest the sensibility of the part be injured. It is however necessary to have several of these torpedos in readiness, because it sometimes requires two or three to effect the cure, or, in other words, the numbness, which is the sign of the remedial effect." Galen and Dioscorides also allude to the same animal. . It would appear from Bancroft, (History of Demerara,) that in Demerara the electric eel is employed in the cure of paralysis as the galvanic or electric machine in Europe; and M. Van der Lott, a surgeon of Essequebo, has published, in Holland, a memoir on its utility in medicine. It is, however, to be observed, that the shock produced by these animals is followed by a trembling of the muscles and a painful feeling of numbness; and that it differs in some degree from that which the voltaic pile, or Leyden jar, occasions, being more like that caused by plates of zinc and silver, upon an abraded part of the arm or hand. After handling the electric eel for some time, and consequently experiencing many shocks of various intensity, the limbs feel a heavy pain, which lasts for more than a day, accompanied with debility of the muscles, and a languor of the whole frame, the effect of irritation of the nervous system. The shock itself, however, given by a full grown and vigorous electric eel, is extremely violent; insomuch, that a person receiving it from a vigorous animal, neither wounded nor fatigued, is so overwhelming, as completely to bewilder the sufferer for the time. "I never remember," says Humboldt, "to have experienced a more terrible blow from the discharge of a Leyden jar of great size, than one

which I received on putting my two feet on a gymnotus which was dragged out of the water. During the rest of the day, I felt great pain in the knees and in almost every joint of the body. A blow on the stomach, a stone falling on the head, a tremendous electric explosion, produce in an instant the same effects; nothing is distinguished, all is vague, when the whole nervous system is thus shocked violently at the same moment."

We need not say that in the pools, lakes, or meers, tenanted by this formidable fish, it reigns supreme; what, indeed, can withstand its assaults? It comes not upon its foe with teeth, nor the common weapons of its race, for then force might be opposed to force; but it deals destruction by the agency of means against which strength and courage are of little avail. But what is remarkable is, that animals, liable to the stroke of its electric weapon, such as fishes, reptiles, etc., which inhabit the rivers with the gymnotus electricus, display no instinct which teaches them to avoid it, while it regards every thing which approaches it as an enemy, and inflicts upon each its electric blow. Hence, few fishes are found, besides those of its own species, in the waters where it abounds; it assaults such as approach it, and kills them even when not requiring food. It hovers over its unsuspicious victims like a thunder cloud, and waiting a moment as if to prepare the bolt, it then hurls its mimic lightning on their devoted heads. This is no exaggerated picture.

Baron Humboldt, on one occasion, put into the tub of water, in which was one of these eels, an aquatic tortoise. The tortoise, with great confidence, and unsuspicious of giving offence, gently made its way towards the fish, and then endeavoured to hide itself under the animal's body. Scarcely, however, had the tortoise touched the eel, before the former received a shock, happily for itself too feeble (the fish being exhausted) to kill it, but strong enough to give it great anguish, and make it retreat with the utmost expedition. From that time, the tortoise never ventured near the gymnotus, the powers of which it had so painfully experienced. It often happens that in fishing with nets, young crocodiles of two or three feet in length, and various fishes are

captured, together with one or two electric eels, all enclosed in the same prison; and it is generally found that all the fishes are dead, and that the crocodiles are writhing in agony. The Indians say, that the young crocodiles have not the power to escape by tearing the meshes of the net, as they would otherwise do, because the eels immediately strike them with paralysis, and so disable them.

Notwithstanding its ferocity, its singular battery, and its savage and serpent-like aspect, the gymnotus is not destitute of docility; it is much less active than our common eel, and it soon becomes accustomed to confinement in a tub or large vessel, eating what is offered to it, and by no means displaying a voracious appetite. Its power of discharging its electric battery is completely under its own control, as it is also in the torpedo, and the strength of the shocks, in a healthy animal, depend upon its will: in wounded animals they are usually more feeble, and sometimes appear to be reduced to the lowest degree, but not always; for it has occasionally happened that persons have handled an apparently exhausted gymnotus for some time, without any shock being experienced, when all at once the animal, as Humboldt experienced, has discharged its electric battery with the utmost severity of effect. Several times, the same traveller was bold enough to hold one of these fishes by the tail, and even pinch it, and received no shock, till his fellow traveller M. Bonpland tickled it on the belly, or on the gill covers, and then he received a terrible stroke, while M. Bonpland felt nothing of the kind; and Humboldt states, that when two persons touch at once the space occupied by the electric apparatus, their fingers being two inches apart, it is seldom that both are affected by the electric explosion at the same time. It depends, indeed, on the will of the animal to which of the objects touching it, it shall direct the electric fluid, or whether it will call up this or that portion of its electric organs into action. When two persons touch the animal, each with a metallic rod, and bring the ends of the rod on the body of the animal to within five or six lines of each other, both are not affected simultaneously; the animal discharges its electricity first through one rod, then through the other, giving a

shock to each holder in succession; and here is a great difference between the natural electric apparatus of the eel, which is under the creature's control, and the artificial Leyden jar. It is found that when tickled on the under surface, on the pectoral fin, on the lips, eyes, and especially the gill covers, that the animal gives the most violent concussions. These parts, indeed, seem to be peculiarly sensitive, and the skin over them is very delicate. The torpedo is only capable of giving an electric shock when its electric organs are touched; not so the gymnotus; it matters not what part of the body be touched, for this creature to communicate the stroke, if it desires to give it; which, if touched on one of the sensitive portions of the body mentioned, it rarely fails to do, unless when actually dying, or completely exhausted, and consequently ill.

The gymnotus electricus, when full grown, measures between five and six feet in length, and its colour varies with age, and the nature of the water in which it dwells. Generally, it is of an olive green, with the under part of the head of a yellow tint mingled with red, and a double row of small excretory openings in the skin from the head to the tail are thus coloured; these openings appear to belong to mucous glands, which secrete the slimy fluid with which the skin is lubricated. The mouth is wide, and the interior, as far as the gullet, is furnished with little teeth disposed in rows, and very closely set; the tongue is fleshy, and covered with papillæ. It may be asked, What is the structure of the apparatus which gives to this eel its terrible powers, and renders it capable of discharging an electric shock of such violence as to throw down horse and man? The organ which produces these singular effects occupies the under part of the tail, or terminal portion of the body, and consists of four longitudinal masses; two large above, two small below, each being composed of a vast number of membranous laminæ, or thin plates, closely set together and nearly horizontal; these plates have their external margin affixed to the skin, and they rise to a level with the vertebral column; they are besides united to each other by an infinite number of transverse small vertical laminæ, and thus are formed a multitude of transverse cells,

or minute prismatic canals, filled with a gelatinous matter, and abundantly supplied with nerves. On these nerves depend their electric power; but how, or in what manner the accumulation of electric fluid takes place, the means which the animal has of discharging it, or not, at pleasure, or in what direction it pleases, and the theory of its production,-these points are all enveloped in mystery. We are presented with nerves, and a large laminated apparatus; and we find that these nerves and this apparatus of plates constitute, in some mysterious manner, an electrogalvanic battery, governed as to its use by volition; but we know no more. How soon are we stopped by impassable barriers in the progress of our investigations among the wonders with which the great field of creation teems! How soon do we discover the limitation of our minds, and their inadequacy to grasp a part, a little part, of the ways and workings of the Almighty!

The sketch on page 363 represents a section of the terminal portion of the body of the electric eel, containing the electrical apparatus in its natural situation, and serves to convey a clear idea of the arrangement of its plates, and the relative magnitude of the upper and lower double series.

M.

CLIMATE AND MONUMENTS OF EGYPT, No. I.

EGYPT, whose history is closely interwoven with so much of the inspired narrative, is distinguished from all other countries by certain peculiarities of situation and of climate to which we have already alluded, and which we now proceed more fully to explain.

It lies between the parallels of latitude which are immediately to the north of the tropic of Cancer, and in both hemispheres and on every part of the earth's circumference, the countries so situated are remarkable for extreme drought and a consequent tendency to sterility. This is peculiarly the case with Egypt. It is a valley hemmed in by two ranges of mountains of no great elevation, extending from south to north, and flanked on three sides by deserts on the east by the deserts of Arabia, interrupted only by the narrow gulf of the Red Sea; to the south and west by the Libyan desert, a vast

expanse of sterile sand which stretches away southward into the very heart of África, and westward to the shores of the Atlantic. It is thus in the centre of the largest tract of uninterrupted desert on the surface of the earth; and, in consequence, rain is well nigh unknown in Egypt. In Upper Egypt, called also the Thebaid, rain was accounted a prodigy: and in the lists of the kings of Egypt, which were prepared by Manetho, a priest of Sibennytus, in Greek, by the command of Philadelphus, he has thought it worth recording that the year before the disastrous invasion of Darius Ochus there was rain in the Thebaid. The same peculiarity has also been noticed by modern travellers. Rain in that district excites astonishment and alarm amongst the inhabitants from the extreme infrequency of its occurrence.

The whole extent of the valley of Egypt is traversed by the magnificent river which is so intimately connected with its entire history, and so familiar to every one whose attention has been at all directed to that country, the Nile. The fertility of Egypt, yea its very existence otherwise than as a tract of desert, depends upon the phenomena connected with this river. The Nile ordinarily rolls a broad majestic stream of clear blue water to the sea, the pleasantness and salubrity of which as a beverage are acknowledged by all travellers, and praised by the inhabitants as far surpassing in excellence any other waters in the world; so much so, that the more opulent among them carry with them the waters of the Nile when they have occasion to visit other countries; and all ranks in Egypt regard the privation of the delicious draughts of their beloved river as one of the greatest hardships connected with absence from home. But regularly every year, about the time of the summer solstice, June 21, the waters of the Nile suddenly change their appearance, and become red and turbid, so that in the course of a few hours its hitherto limpid stream seems to be turned into a river of blood. There is no atmospheric change in Egypt to account for this. The burning sun, the clear sky, and the dry atmosphere for which it is remarkable at all times, appear at this season to prevail with more than usual intensity. After this phenomenon has continued for a few days, the waters gradually increase within the banks of

the river. This increase proceeds with perfect regularity until about the middle of July, when they begin to overflow the banks; and by the 20th of the following month, Egypt presents the astonishing appearance of a vast sea, spotted over with villages and towns, and traversed in various directions by causeways which have been laid on mounds thrown up for the purpose of preserving the communication between them. The inundation continues increasing until the time of the autumnal equinox, when it begins as gradually to diminish; and before the end of November, the Nile has once subsided within its banks, and again its clear blue waters sparkle in the burning sun of Egypt.

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The industry and skill of the inhabitants have at all times been directed to the diffusion of these fertilizing waters over the greatest possible extent by means of canals and embankments; and these their efforts have been greatly assisted by the natural conformation of this most singular country. The surface of Egypt is convex; it rises gradually from the mountains that bound it to the east and west to the bed of the river, which runs like a deep furrow along the summit of the convexity; a circumstance of course highly favourable to the distribution of its waters during the inundation. Many of the ancient kings of Egypt were held in grateful remembrance by after ages on account of their efforts in the construction of lakes, canals, and mounds for this purpose; and there is a very distinct allusion to them in the prophecies of Isaiah, chap. xix. 5-7. We have already explained the entire dependence of the fertility of Egypt on the inundation, and therefore sufficiently accounted for this anxiety in the wide diffusion of its waters, which communicate a fertility unparalleled elsewhere on the earth's surface to a country which without them would be a desert; the excessive dryness of the atmosphere and the all but total absence of rain, excluding the possibility of vegetable life there; so that one and not the least of the marvels of Egypt is, to see these two extremes of fertility and barrenness in contact with each other.

Another equally extraordinary effect of the extreme dryness of the atmosphere in Egypt demands our particular

attention. Moisture, the great agent in decomposition, has been entirely abstracted from the atmosphere by the burning sands of the desert, and consequently time, whose corroding tooth so rapidly destroys the works of men's hands in other countries, passes_over the monuments of ancient days in Egypt almost without effecting any perceptible change in them. The paintings that cover the walls of temples which have been for the most part roofless for nearly two thousand years still remain undefaced; the colours are perceptible, and in certain cases they have even retained much of their original freshness. If such be the case with works of so fugitive and fragile a character as these, this perfect preservation will, of course, be still more conspicuous in the granite, basalt, and hard limestone of which the Egyptians made so free a use in their constructions. The sculptures and inscriptions on these substances seem to have undergone no change in the long period that has elapsed since many of them were sculptured; so that the fragments of temples which were levelled to the ground by Cambyses five hundred years before the Christian era, have not yet lost the polish they possessed when they first issued from the artists' hands. Thus the combination of extreme freshness and extreme antiquity in its works of art is another of the marvels of Egypt. This is made very conspicuous when some accidental cause affords the opportunity of measuring, as it were, the period that has really elapsed since their execution. The obelisk that is still erect among the ruins of Alexandria retains much of the freshness, sharpness, and high polish of its first execution on its north and east faces : but the minute particles of sand with which the air is charged in passing over the desert have entirely defaced its south and west sides by beating against it during the sixteen hundred years in which it has stood in its present position; for probably about that time, it was removed to Alexandria from some other city where it had been originally

erected.

The same anomaly is even more observable in the excavations in the sides of the mountains, whereby the Egyptians have perpetuated the proofs of their skill and industry. On first surveying the immense cavern temple at

Ipsambul, in Nubia, the spectator might well imagine that the artists were still at work in it. It is impossible that the white of the walls can at any time have been purer or more perfect, the outlines of the figures sharper, or the colours more brilliant than now; and this impression is strengthened when he comes to that part of it where the tracings and first outlines show that this great work was never finished. But the black dust that, to the depth of many inches, covers the rocky floor on which he treads, and into which the doors, the door posts, and internal fittings of the temple have long since corroded and mouldered, soon convinces him of his mistake, by showing him demonstrably how many ages have rolled away since the hands by which these wonders were accomplished have been motionless in the grave.

This congeniality of the climate of Egypt to the perpetuation of works of art has preserved them to our times in numbers which are truly astonishing, when we take into account the disastrous history of the downfall of that ancient monarchy, the invasions, the civil wars, and the successive conquests by which her original population was well nigh annihilated; and still more when we consider that for the last sixteen hundred years they have been entirely neglected by the inhabitants, and left in great measure to dilapidation and ruin.

These remains of the departed greatness of Egypt consist generally of places for religious worship and ceremonies, and for civil assemblies. The site of almost every city of note in upper or southern Egypt is marked by the ruins of a temple or palace temple, which was at once the residence of the monarch, and the place where the solemn religious and civil assemblies of the chief estates in Egypt were held. These ruins are covered with reliefs, generally coloured, and representing the idols to which they had been dedicated receiving the homage of the kings by whom they had been founded; and also the battles, sieges, and other events of the wars, out of the spoils of which these acts of munificence were performed. These pictures often cover a vast extent of wall, and are crowded with figures in action, executed with much spirit and fidelity; the costume and the peculiarities of feature and