Galvani having been dissecting some frogs, hung their legs on the iron palings of his door-way. A thunder cloud happening to lower over Bologna at the time-for Galvani lived at Bologna-all the dead frogs' legs began to kick. Alas! the poor frog, the barren honor of having lent a "leg" to the discovery of galvanism, little compensates for electrical experiments he has since been obliged to participate in against his will. Leeches and snails are also delicately susceptible of electric influences. When almost any two pieces of different metal are brought into contact, with moisture between them, electricity is evolved; this, indeed, being the principle on which voltaic batteries are constructed. Well, if a crown-piece be moistened, then laid flat upon a plate of iron or zinc, and a leech dropped on the crown-piece, the little fellow will be almost as securely imprisoned as if he were tied by the tail. He may kick and wriggle, and try to be off, but immediately he extends his snout over the edge of the silver, and drops it upon the outside metal, he receives a shock which makes him glad to shrink back again; and by varying the form of arrangement, taking an annular piece of silver, and laying it upon another annulus of iron or zinc, the protective influence of electricity may be brought to bear for the protection of an object placed within the charmed circle. In this way we can, if we are so minded, protect any little vegetable of which snails are fond from their insidious advances. Animal electricity assumes its most curious manifestation in certain fish, which discharge shocks at will, for the purposes of offense and defense. Three fish are noticeable in this respect; one, a sea-fish, (the torpedo ;) the others, freshwater fish belonging to hot countries: these latter are the gymnotus electricus, and the silurus electricus, respectively. In all these creatures the electricity is developed by specific organs, which, being dissected, show a configuration something like that of a voltaic battery. The torpedo is a gristly flat fish, one of the ray tribe it is common to the Mediterranean, and its powers have been known from times of great antiquity. Long before the real source of its power was dreamt of, certain Roman physicians proposed touching the torpedo, and receiving its shock as a curative means for the same class of diseases which are treated by electricity now. Much more formidable than the torpedo is the fresh-water shock-giver-the gymnotus electricus, or electric eel, found in some of the rivers of the hottest regions of South America. Several specimens of the gymnotus have been imported to England at different times, and made the subject of experiment. There once was a doubt whether the shock-giving power of the fishes indicated really depended upon electricity of precisely similar kind to that evolved by our machines. As regards the torpedo and the gymnotus, these doubts have long ceased to exist, and though the silurus electricus has not. given equal opportunities for experiment, no one doubts that the shocks communicated by it are really dependent upon electricity. The silurus, however, is a smaller animal, and altogether a more contemptible foe than the gymnotus, only measuring about twenty inches long; whereas a full-grown gymnotus will mea sure three or four feet, or in extreme cases even more. Some idea of the power of the gymnotus may be entertained from the means used to disarm them, and to catch them when their capture is desired. Humboldt relates that fords have sometimes to be abandoned for fear of the gymnoti which infest them, and he graphically describes the means employed to catch them. A number of wild horses being driven into the river, and prevented getting out again until they have accomplished their task, soon awaken the gymnoti from their lazy slumbers. They ascend from the bottom, glide under the horses, touch them, and dive again. It is only a touch; but such a touch! The horse neighs with fright, and kicks and plunges. Other gymnoti now touch him, returning to the attack again and again. Many of the horses are drowned in the unequal struggle; but each attack costs the fish an expenditure of force. They, too, are at length exhausted, float like dead things near the surface of the water, and may be caught with impunity. What is this wonderful agent-what is electricity? We can not tell. Nothing is more common than to hear it attributed to the action of a fluid to which the term electric fluid is applied. Now this is delusive. Not only is there no evidence of the existence of such fluid, but modern electricians are inclined to ignore its ex-| istence altogether. True it is that most of the functions of electricity convey the idea of something passing-of something flowing on; but this is no proof of the existence of a specific fluid. Who has not gazed on a field of corn in a windy day, and seen wavelike forms careering over its surface? The waves pass on, but each corns-talk remains where it originally was, and thus philosophers believe it to be with electricity. In other words, they conceive it to be a peculiar motion set up amongst the particles of matter, rather than a specific something contained in matter. (within limits) of that substance. Thus wire may be so small that a charge of electricity will simply melt it without passing through, or the wire may be so much larger than requisite, that the increase of dimensions above the necessary point will not accelerate the passage of electricity. Moreover, the material wherewith a conducting body is surrounded modifies the passage of electricity; for example, it will not traverse a subaqueous cable with the same facility that it traverses one surrounded by air. In an experiment performed by Professor Wheatstone-too complex for explanation here -it was found to traverse a copper wire with the amazing velocity of at least four hundred and ninety millions of miles in a second of time! The puny mind of man sinks down powerless before the contemplation of such tremendous figures, and we rise with new wonder and reverence at the mysterious powers which God has The rapidity with which the electric influence is transmitted through conducting bodies is astounding; but it is a fallacy to say, as is sometimes done, that electricity passes at any definite rate, abstractedly. The fact is, that its velocity of traveling not only differs for every peculiar substance, but for every varying dimensions set around us. HOW TO EAT WISELY.-Dr. Hall, in body gradually, and by safe degrees, to his journal, gives the following advice: regain its usual vigor. Then, in a couple "1. Never sit down to a table with an anx- of hours, you may take a full meal, proious or disturbed mind; better a hundred- vided it does not bring it later than two fold intermit that meal, for there will then hours before sundown; if later, then take be that much more food in the world for nothing for that day in addition to the hungrier stomachs than yours; and be- cracker and tea, and the next day you sides, eating under such circumstances will feel a freshness and vigor not recentcan only, and will always, prolong and ly known." No reader will require to be aggravate the condition of things. advised a second time who will make a 2. Never sit down to a meal after any in trial as above, whilst it is a fact of no untense mental effort, for physical and men- usual observation among intelligent phytal injury are inevitable, and no man has sicians, that eating heartily, and under a right to deliberately injure body, mind, bodily exhaustion, is not unfrequently the or estate. 3. Never go to a full table cause of alarming and painful illness, and during bodily exhaustion-designated by sometimes sudden death. These things some as being worn out, tired to death, being so, let every family make it a point used up, done over, and the like. The to assemble around the family board with wisest thing you can do under such cir- kindly feelings, with a cheerful humor cumstances is to take a cracker and a cup and a courteous spirit; and let that memof warm tea, either black or green, and ber of it be sent from it in disgrace who no more. In ten minutes you will feel a presumes to mar the ought-to-be blest degree of refreshment and liveliness which reunion by sullen silence, or impatient will be pleasantly surprising to you; not look, or angry tone, or complaining of the transient kind which a glass of tongue. Eat in thankful gladness, or liquor affords, but permanent; for the away with you to the kitchen, you gracetea gives present stimulus and a little less churl, you ungrateful pestilent lout strength, and before it subsides, nutri- that you are! There was grand and good ment begins to be drawn from the sugar philosophy in the old-time custom of having and cream and bread, thus allowing the a buffoon or music at the dinner-table.. Ir is related of some savages, in the fifteenth century, that when they for the first time beheld a ship approaching their shores, they imagined it to be an immense animal skimming the surface of the waters, whose wings were represented by its sails, and whose boats they regarded for a time as its offspring. Similar misconceptions have occurred in more recent times. About thirty years ago, for example, the crew of a British ship that had been some years in the South Seas, and was homeward bound within a week's sail of England, witnessed a phenomenon not less astonishing to their apprehension than a ship had proved to that of the simple natives of a remote region. The sensation it excited is not to be easily conceived; but the notice of the occurrence, as recorded in the phraseology of the ship's logbook, may possibly assist the conception. The following is the entry: "At sunset, dead calm; cloudy and hazy; no sail in sight. At 6.30, saw a black spot on the horizon, bearing W.S.W., which we at first supposed to be a vessel more fortunate than ourselves with a breeze; and this seemed the more probable, from its enlarging in bulk as if advancing toward us. At seven o'clock it had increased considerably, but was wholly unlike a vessel in its form, although a good height above the surface of the waters, and we could perceive that its form altered repeatedly. By several of the crew it was thought to be a very large whale, and the variation in its aspect arose from its spouting up water in its gambols upon the surface. Got a gun ready to fire at it, if it should come within range; but we soon found that it was taking an oblique direction across our stern. We could now, with the telescope, distinctly perceive the waters breaking and foaming about it from the impetuous action of its unwieldy body. The whole crew had become greatly excited, from an apprehension that it might turn upon us. Kept the gun pointed at it, ready to At fire, and got another gun loaded. 7.15 it was broad on our larboard quarter, bearing N.W. by W. It now loomed still larger through the haze of evening, but with as little resemblance to a whale as to a ship; and from the rapidity and peculiarity of its motions, it seemed to partake more of the feathered than of the finny tribe, unable, perhaps, from some whilst the violent action of its wings and cause or other, to sustain a higher flight, feet must have occasioned those frequent bodies of water it cast upward, and which left behind it long streams of spray. Unfortunately, the obscurity of evening deprived us of a distinct view of its general form, but its color appeared to be of an uniform black. At 7.30 it was three points before our larboard beam, pursuing the same direction; and at 7.45 it was wholly obscured from our sight. All hands on board witnessed this extraordinary creature, and were greatly alarmed at its extraordinary bulk and action, its furious velocity, and its frightful aspect during its transit across the calm waters of the Atlantic. board were so affected that they went to Two or three of the men on prayers, fervently testifying their conviction, by repeated asseverations, that the mysterious object could be nothing but some supernatural appearance. Calm all night, keeping a good look-out, but no further appearance of the stranger." To this entry succeed the names of the master and crew. England, the imagination of all on board, By the time the ship had arrived in growing by what it fed upon, had so worked upon their credulity, that even the captain, endowed probably with a larger share of intelligence and experience than his companions, having never before seen, read, or heard of so prodigious a mass of vitality, had persuaded himself that his name, with the names of his crew, and that of his ship, had established a famous notoriety, which could not fail to be thenceforth associated with a recorded marvel. An elucidation, however, as surprising as it was unexpected, awaited them on their arrival. The monster had actually been brought into the port at Liverpool, where it was being exhibited. Thousands of persons, men, women, and children, had heard of it, seen it, and become familiar with it, and the inhabitants generally had ceased to regard it with astonishment or special interest; for while the skipper and his crew had been catching whales in the South Seas, its species, its habits, and even its organization, had been duly investigated and popularized; and in the meantime vulgar phraseology, for want of a better term, had named it a steam-ship.* gaze directed seaward, their eye-balls were ready to start from their sockets, while they looked affrightedly upon the swift approach of some incomprehensible monster, which had been stealthily advancing upon them unperceived. All now was confusion: invocations, vociferations, and even imprecations mingled in a general and indescribable hubbub, while all hands were summoned to get one boat over the side, and to drag up another that had been towing astern. Hasty glances only could be given at the demon advancing with such appalling strides―rather, however, to measure its distance than to examine its features. The boats were not sufficient for the whole crew, who were soon rushing headlong over the vessel's side to gain them. A brief conflict ensued among the competitors, the strong against the weak, till both boats hurriedly shoved A few years elapsed. A privateer lay becalmed off the shores of the island of Trinadad. Her sails, drooping from the yards and cringles that sustained them, seemed languishing for a breeze to neutral-off, leaving those who were abandoned to ize the intensity of the glowing heat to seek safety by plunging into the sea, to which they were exposed. The steers- follow by swimming, or to sink by exhausman's vocation was suspended, and the tion and fright. Every nerve was strained helm left to itself. Some spare sails were by the rowers in the boats, and every extended above the deck, to serve as a kind of utterance was employed to stimutemporary awning over the heads of the late them in their purpose. As the dishybrid crew of half-caste desperadoes, tance was short, they soon reached the who cared little for sun, moon, or stars, shore, and with one bound the whole of for the welkin above or the depths be- the living freight reached the strand, and neath, and as little for danger in any form, scampered as fast as legs could carry them till a breeze should bring it or enable into the adjacent forest. With the swimthem to seek it. They were promiscuous-mers, hope was now yielding to despair; ly disposed in listless inaction about the deck, after partaking of a repast which had imposed upon the cook the most arduous duties, and had also stimulated their own bibulous propensities. Some were smoking their cigars, but most of them were dozing away their time. It was a season of general repose. That beautiful island and the opposite shores of the continent were slumbering beneath the pink gauze of an ardent atmosphere, and not a cloud was to be seen in the keen azure above, to cast a shadow upon the bright smooth waters. While Nature was resting, why should not they also have a nap? And so they smoked and napped, until at length they were startled to their feet by a sudden exclamation of one of their number, who had been sleepily looking out upon the glassy face of the deep. As their attention was roused, and their *This was, we believe, the first steam-ship that crossed the Atlantic, and was named the "Fulton," belonging to New-York. their ears had caught the fearful sounds emitted by the belching monster, which seemed to convey a fearful presage of their fate, and paralyzed their energies. Still, however, they continued to strike out, as the hissing, whizzing, gurgling, tremulous noise increased. Their nearer approach to the beach encouraged them, and they strove also to animate one another, but all in vain; it was too late; their spirits gave way within them; the wild, confused sounds came louder upon their ears, and they felt that they were already within the monster's grasp, as the first long swell of the agitated waters overtook them, and carried them half senseless upon the sands. The unknown and dreaded object steamer - had meanwhile whisked past them, and round the bend of the coast, heedless of the abandoned vessel, and of the ignorant terrors which its first appearance in these waters had produced. a Years rolled on, and steam was astonishing the natives of other regions, till one day it penetrated the West-African Neither inclined to the speculative, or that, while scanning the hazy horizon with his glass, or in occasional fits of abstraction, his mind hovered over the small "farms" around the base of the hill, with their yams, and cassada, and corn, and his "broder Africans" at their desultory labor, he should have indulged a good deal in monologue. Hence we can picture him, on the day in question, soliloquizing somewhat in the following fashion: mist on a visit to Sierra Leone. its name nor its distinguished rank appeared as yet in the category of expected or casual arrivals, at a station on that coast, near which the writer then resided. "Ships, "brigs," and "schooners," were alone on the visiting list, as worthy of the honor of a signal from the functionary whose office it was, as they came in sight, to announce them from his bureau, on the top of the hill about two miles from town and harbor; whilst the prominence of the spot itself, with the whitewashed lighthouse beneath it, was as significant as a street-door into an entrance-hall, for the guidance of such vessels in a safe approach toward the anchorage. Still, as they necessarily came end foremost to this particular point of the coast, their precise denomination was not always to be readily distinguished; but as a mast, like a tooth, is more easily taken out than put in, the signal-man made it a rule to announce a ship first, and then, if necessary, make her into a brig. This notable was an eccentric character; he was a strict disciplinarian, had served in the Ashantee war as a private in the African corps, had graduated in West-India regiments till he acquired the dignity of a sergeant, and eventually became entitled to a "good-service pension" of six pence a day, with the honor of still serving the British crown as "captaingeneral and commander-in-chief," of a signal-post and its et ceteras. He was, nevertheless, strictly speaking, a "retired officer." His locality made him so. Here upon the rugged rocky platform of his domicile, hemmed in by high coarse grass intermixed with the prickly cactus and a variety of wild shrubs, Phoebe his wife, a few fowls and his telescope, one single gun and a flag-staff, were the sole ministers to his social enjoyments. Now and then, it is true, a chance visitor came to stop, for the sake of an airing or the beauty of the view, to whom he would show his certificates of service, advert to the origin of the distinction he bore in the army under the soubriquet of "Trump," or particularize the several occasions, during the reign of George III., on which he had shared in honor of firing a "furious-joy" on his majesty's birthday. No wonder that, with the wide ocean as the prescribed sphere of his daily contemplations, his philosophy should have "I tink so," she replied. "Dere no wind; I no see noting; ebery ting sleep; I go sleep too. 'Spose you eye catch any one come, call me ; hearey ?" "Berry well," responded Phoebe. Still he had been on 66 guard" so often in his life, that it had become a habit; and that the wind might not catch him napping, he instinctively took another glance at the horizon-now to behold something! 'Berry odd," he exclaimed, "no see dat biffore!" But he had seen that singular phenomenon in the sky which is called the "bull's-eye cloud," and known to presage a tornado, and it seemed that here it was fallen into the sea in the middle of the dry season. His glass had never materially deceived him, but his suspicion now fell upon it; his hand, too was not so steady as usual, and he experienced a strange pricking sensation about his cranium as he gazed steadfastly through the tube. It certainly was warm and misty! "Berry odd," he repeated," him move, him move-come dis way, too, I tink; no wind dere-sea smoode-no hab sail-no hab mast; dat no ship, no brig, no schooner, berry odd. Phœbe, come here!" And Phoebe came. "Phœbe," he continued, "you no hearey ob dat island long way up da Melli |