Chapter VI: Part 6

Its distance from the sun is nearly eighteen hundred millions of miles, or more than nineteen times that of the earth. Its density, as compared with that of the earth, is nearly as twenty-two to one hundred; so that its entire weight is more than eighteen times that of our planet. Finally the force of gravitation near its surface is such, that falling bodies descend only through fourteen feet during the first second, instead of thirty-two feet as with us. Herschel afterwards discovered no fewer than six satellites, or moons, belonging to his new planet.

The announcement of the discovery of the Georgium Sidus at once made Herschel’s name universally known. In the course of a few months the king bestowed on him a pension of three hundred pounds a year, that he might be able entirely to relinquish his engagements at Bath; and upon this he came to reside at Slough, near Windsor. He now devoted himself entirely to science; and the construction of telescopes, and observations of the heavens, continued to form the occupations of the remainder of his life. Astronomy is indebted to him for many other most interesting discoveries besides the celebrated one of which we have just given an account, as well as a variety of speculations of the most ingenious, original, and profound character. But of these we cannot here attempt any detail. He also introduced some important improvements into the construction of the reflecting telescope--beside continuing to fabricate that instrument of dimensions greatly exceeding any that had been formerly attempted, with the powers surpassing in nearly a corresponding degree, what had ever been before obtained. The largest telescope which he ever made, was his famous one of forty feet long, which he erected at Slough for the king. It was begun about the end of the year 1785, and on the 28th of August, 1789, the enormous tube was poised on the complicated but ingeniously contrived mechanism by which its movements were to be regulated, and ready for use. On the same day a new satellite of Saturn was detected by it, being the sixth which had been observed attendant upon that planet. A seventh was afterwards discovered by means of the same instrument. This telescope has been taken down and replaced by another of only half the length, constructed by Mr. J. Herschel, the distinguished son of the subject of our present sketch. Herschel himself eventually became convinced that no telescope could surpass, in magnifying power, one of from twenty to twenty-five feet in length. The French astronomer, Lalande, states that he was informed by George III. himself, that it was at his desire that Herschel was induced to make the telescope at Slough of the extraordinary length he did, his own wish being that it should not be more than thirty feet long.

So extraordinary was the ardour of this great astronomer in the study of his favourite science, that for many years it has been asserted, he never was in bed at any hour during which the stars were visible. And he made almost all his observations, whatever was the season of the year, not under cover, but in his garden, in the open air--and generally without an attendant. There was much that was peculiar to himself, not only in the process by which he fabricated his telescopes, but also in his manner of using them. One of the attendants in the king’s observatory at Richmond, who had formerly been a workman in Ramsden’s establishment, was forcibly reminded, on seeing Herschel take an observation, of a remark which his old master had made. Having just completed one of his best telescopes, Ramsden, addressing himself to his workman, said, “This, I believe, is the highest degree of perfection we opticians by profession will ever arrive at; if any improvement of importance shall ever after this be introduced in the making of telescopes, it will be by some one who has not been taught by us.”

Some years before his death, the degree of LL.D. was conferred upon Herschel by the University of Oxford; and in 1816, the Prince Regent bestowed upon him the Hanoverian and Guelphic Order of Knighthood. He died on the 23rd of August, 1822, when he was within a few months of having completed his eighty-fourth year.

We have been thus particular in the enumeration of particulars in the lives of those great men, who have cultivated this sublime science, for the purpose of availing ourselves of a suggestion furnished by Dr. Priestly, who observed, “That we could only see Newton in two points of his career: at the bottom of the ladder, and at the top; having left no account of his progress, it appeared as though he had broken the steps by which he had ascended, that none should follow.”

From the facts collected by the many eminent men whose names have ornamented our pages, we are enabled to state the following particulars concerning that part of the universe denominated the Solar system.

The _Sun_, a luminous body diffusing light and heat; whose diameter is computed at 890,000 miles; diurnal rotation on axis 25 days 6 hours; performs his annual revolution in orbit in 365 days 6 hours; progressive equatorial motion in orbit per hour, 3818 miles.

_Mercury_, whose diameter is 3,000 miles, revolves in an orbit 36,481,448 miles from that of the sun. He performs his annual period round that planet in 87 days 23 hours; his hourly equatorial motion in orbit is 109,699 miles.

_Venus_,--her diameter is 9,330 miles; revolves in an orbit 68,891,486 miles distant from the sun; performs her annual revolution in 224 days 17 hours; diurnal rotation on axis 24 days 8 hours: hourly equatorial motion in orbit 80,295 miles.

The _Earth_,--its diameter 7970 miles; distance of orbit from the sun 95,173,000 miles; revolves on its axis once in 24 hours; performs her annual period round the sun in the same time the sun completes his revolution; hourly equatorial and progressive motion in orbit 80,295 miles.

The _Moon_ is a satellite to the earth; her diameter is 2180 miles; her diurnal rotation on axis is performed in 29 days, 12 hours, 44 minutes; she performs her annual revolution round the sun in precisely the same time as does the earth, her superior planet; her motion in orbit per hour is 22,290 miles.

_Mars_,--his diameter is 5400 miles; distance from the sun, 145,014,148 miles; annual period round the sun 671 days, 17 hours; diurnal rotation on axis 19 days, 12 hours, 44 minutes; hourly motion in orbit 55,287 miles.

_Jupiter_,--his diameter 94,000 miles; distance from the sun 494,990,976 miles; annual period in 11 years, 314 days, 18 hours; diurnal rotation on axis 9 hours, 56 minutes; hourly motion in orbit 29,803 miles.

_Saturn_,--his diameter 78,000 miles; distance from the sun 907,956,130 miles; annual revolution in orbit 22 years, 167 days, 6 hours; hourly motion in orbit 22,101 miles.

It should be observed that Jupiter has four moons, or satellites, with a large and very luminous belt at a great distance from his surface. Saturn also has seven moons, with a very luminous ring about 21,000 miles broad, from its uppermost to its undermost edge; and about the same distance from its surface.

_Georgium Sidus_,--the distance of the orbit from the sun, 1,758,000,000 miles; annual revolution 28 years, 289 days; diameter 56,726 miles; has two satellites, or moons.

About 1801, 2, and 4, there were discovered three other small planets in the system of the sun, called _Vesta_, _Juno_, and _Pallas_.

The fixed stars composing the _Zodiacal Signs_, are divided into twelve constellations, one to each month; which asterisms were discovered by Flamstead to consist of the following number of stars to each:

_Aries_, the Ram, 66; _Taurus_, the Bull, 141; _Gemini_, the Twins, 85; _Cancer_, the Crab, 83; _Leo_, the Lion, 95; _Virgo_, the Virgin, 110; _Libra_, the Scales, 51; _Scorpio_, the Scorpion, 44; _Sagitarius_, the Archer, 69; _Capricornus_, the Goat, 51; _Aquarius_, the Water-Carrier, 108; _Pisces_, the Fishes, 113.

A comparative idea of the extent of the works of Omnipotence may be perhaps collected, on our being informed, that the sphere where the fixed stars appear, is presumed to be placed far beyond the most remote planetary orbit; and that some of them are supposed to serve as suns to illumine other systems, or worlds, to us unknown.

NAVIGATION.

The sacred records inform us that the ark of Noah was the first ship, and produced by the invention of the great Architect of Nature himself; and “though some men have so believed,” says the learned and ingenious Sir Walter Raleigh, in his “History of the World,” “yet it is certain the world was planted before the flood, which could not be performed without some transporting vessels. It is true, and the success has proved that there was not any so capacious, nor any so strong, as to defend themselves against so violent and so continued a pouring down of rain, as the ark of which Noah was the builder, from the invention of God himself. Of what fashion or fabric soever were the rest, with all men they perished according to the ordinance of God.” And it appears extremely probable that those testimonials, whereof Ovid speaks of former existence, were remains of ships wrecked at the general flood.

There can be no question that the Syrians were the first maritime power in the world, as well in point of time as importance;--but of what species of construction their vessels were, we are not informed. Their merchants trading to the Eastern Indies, as they did for Solomon; to Ophir, whence they brought gold; and also to this country for tin, and their having made three distinct descents upon America, will enable us to maintain this our opinion. After them the Greeks, a people living chiefly on the shores of the Hellespont and Ægean seas, with many islands in the Mediterranean, Adriatic, and Archipelagion Seas, besides their possessions in Asia Minor, and their commerce with the European Continent, obtained the next power by sea. We read indeed, that Minos, the famous Cretan sovereign and legislator, who lived two descents before the Trojan war, sent out shipping to free the Grecian seas of pirates; which shows, as Sir Walter Raleigh ingeniously infers, that there had been trade and war upon the waters before his time also.

The next in point of time and importance on record was the highly renowned expedition of the Argonauts for the golden fleece to Colchis, a country of Asia, on the Euxine sea. Immediately after this was the colonization of Cyrene, in Africa, by Battus, one of the companions of Jason, in his Colchian expedition. Shortly afterwards, the Grecian states united against Phrygian treachery and the abuse of Grecian hospitality; forming another most memorable epoch in the history of the world. We are informed the Grecian Neptune, or as mythology styles him a God of the Saturnian family, for the great service he did his father, Saturn, or Noah, against the Titans, had the seas given to him. History informs us that the first inventor of rowing vessels was a citizen of Corinth; and likewise that the first naval war was between the Samians and Corcyrians. The history of Ithicus, translated into Latin by St. Jerome, affirms that Griphon, the Scythian, was the inventor of long-boats; and Strabo also gives the honour of the invention of the anchor to another Scythian, the famous Anacharsis, whilst Greece herself by her historians, ascribes its invention to Eupolemus. Also, it is said, that Icarus invented the sail, and others, various other pieces of the component parts of ships and boats. The specification of such other imperfect memoirs, many of fabulous appearance, may be of no great importance.

It appears certain that among the four sons of Javan, the son of Japhet, the grandson, and other the posterity of Noah, who peopled the “Isles of the Gentiles,” the Grecian Islands must long before the days of Minos have used those seas, from the insular nature of their inhabitants. And it certainly does not appear extravagant to us, to presume that this people were among the first who navigated the seas. Mankind in various parts of the world, being stimulated by the same necessities, urged by the same wants, and possessing the same means, might probably produce similar inventions to each other. Most, indeed, had occasion to navigate lakes, and cross rivers. They accordingly constructed such machines as would answer their purpose of passage or migration. So were rafts and canoes, formed of canes, osiers, twigs, &c., where they grew, which they fashioned like boats, and then covered with skins of various animals; others formed rafts of wood; whilst some others fashioned canoes, having hollowed out trees for that purpose. One way or other, each people thus possessed a marine, proper for their purpose it is true, but in various degrees of excellence. This was the case with Greeks as well as barbarians of all nations; all these people, excepting the immediate descendants of Noah, might, perhaps, lay a feasible claim to the honour of the original invention of these articles; and, having never seen such, they virtually have each a good title to the distinction. Indeed, many of them might have taken the idea for such invention from the policy of certain animals, and the nature of others; to instance the sagacity of the beaver and his raft, and the little nautilus with his swelling sail: hence they might have adopted from that animal, and that piscatory insect, the idea of a raft, and also of a vessel with a sail.

In latter days we find the Teutonic Saxons first came to this country, according to Mr. Turner, the Anglo-Saxon historian, in vessels they called _cyules-kells_ by Sir Walter Raleigh. Marine vessels have borne a variety of names, as well as of numerous figures, from the gondola of the Venetian to the canoe of the Esquimaux,--the British man-of-war to the ponderous bonaventure in which the Doge annually espouses the sea.

All those nations, too, through whose hands the maritime power has passed, from time to time, as they have been instructed by experience, or taught by necessity, might repeatedly have made additions and improvements in naval architecture: some calculated for mercantile utility, while others have only attended to warlike strength, and some to answer both purposes, like our Indiamen. But now, the British navy, being supplied with the best materials, and having as ingenious workmen as any, with the addition of the warlike children of the soil, may openly defy all nations, and proudly claim the sovereignty of the seas where her flag has been flying ’midst the battle and the breeze for so many years.

But the most important improvement in Navigation--propelling vessels by steam--has been left to our own times. The steam-engine was first applied to small vessels for the coasting or river trade; but it has now increased to vessels of the largest size,--in fact, the most part of the British navy are steamships. In former times before the introduction of this valuable auxiliary, the passage between England and America was tedious and uncertain, sometimes taking months, but rarely less than from four to six weeks, according to the state of the weather; but now the case is altered. There are a regular line of steamships, one of which leaves Liverpool every week, and the voyage is performed with almost positive certainty in from twelve to fourteen days, independent of the rude Boreas, or the boisterous Atlantic. These vessels are of the largest size and handsomely fitted up for the accommodation of passengers.

LIGHT-HOUSES.

A light-house, in marine architecture, is a building, or watch-tower, erected on the sea-shore, to serve as a land-mark to mariners, on a low coast, by day, and, in any situation, to inform them of their approach to land in the night;--being of most essential utility in causing them to take soundings, avoid shoals, rocks, &c.; or else it is a building erected on a rock in the sea, which, from its situation, would be extremely dangerous to vessels, were not some intimation given of the existence of a rock, where it is locally situated. Of this latter description is the celebrated Eddystone light-house, off Plymouth.

Although this species of architecture is not likely to have been so general in extreme antiquity, because it could not have been essentially necessary to any except to those nations who, from the proximity of their situation to the coast, or other circumstances, pursued maritime concerns; or to those whose connexions rendered the encouragement of the marine of other nations important.

The oldest building of this description, which we believe to be upon record, is the famous Pharos erected on the Egyptian coast, which, being very low land, and exposed entirely to the almost constant west winds coming up the Mediterranean from the vast Atlantic, must, of necessity, have made the port of modern Alexandria, anciently called Dalmietta, very dangerous. It was originally erected by Ptolemy Philadelphus, for the encouragement and convenience of the Phœnicians, who were accounted the foreign factors of that empire; as the Egyptians possessed an unconquerable aversion to the sea, and therefore they never obtained its sovereignty: whilst the former people were the first who obtained the supremacy of that sea.

The island upon which Pharos stood, in the time of Homer, in his simple geography and estimation, was said to be one day’s sail from the Delta; whereas, since the foundation of Alexandria, it was only a mile in distance, and was even joined to the mainland by a mole, having a bridge at each end; or according to some authors, in the middle. The tower was, if report be true, justly entitled to the appellation it obtained--one of the seven wonders of the world; and it is reported, that the light from it has been seen at the distance of a hundred miles; which, assuredly, appears improbable, because the convexity of the earth, we think, would not permit. Its height must have been, at least, 2,400 feet, or 800 yards from the base.

We are enabled to furnish the following particulars of this famous structure. It was built by order of that patron of learning and the arts, Ptolemy Philadelphus, by that eminent architect, Sostrates, who constructed many of the public buildings in Alexandria. It is said to have cost Ptolemy eight hundred talents! Respecting its mode of construction, it was raised several stories one above another; each was decorated with columns, balustrades, and galleries of the finest marble and most exquisite workmanship; and some have even said that the architect had furnished the galleries with large mirrors, by which shipping could be seen at a great distance. However, respecting this edifice, once so famous, that its very name, Pharos, was considered as a common term for all other constructions for the same purpose, it is now said, from Saracenic ignorance and brutality, aided, perhaps, by the assistance of the common leveller, Time, that nothing now remains of this once elegant edifice, but an unsightly tower rising out of a heap of ruins, the whole being accommodated to the inequality of the ground on which it stands, and being, at present, no higher than that which it should command. Such as it is, there is now a light, we understand, usually maintained. There is also an island, which was called Pharos, in the Adriatic sea, on the coast of Italy, opposite Brundusium, for the same reason: likewise the celebrated colossal statue of Apollo, at Rhodes, answered the same purpose, and occasionally had the same appellation, as had a river of Asia, in the environs of Cilicia and the Euphrates. This last consideration brings us to the etymology of the word, as Ozanum says, “Pharos originally signified a strait, as the Pharos of Messina.” Of every description of light-houses yet known, there is none more famous than that called Eddystone, with a description of which we shall conclude this article.

Mr. Winstanley’s light-house was begun upon the Eddystone rock in 1696, and was more than four years in building, from the numerous interruptions of the wind and the element he had to contend with, the violence whereof is truly alarming, occasioned by that rock being exposed to every wind which comes up the vast Atlantic, and that tumultuous sea, the Bay of Biscay. These obstacles were considerably increased by the shape of the rock itself, having a regular slope to S.W., and from the very deep sea in its vicinity, it, therefore, receives the uncontrolled fury of those seas: meeting with no other object whereon to break their vehement force, the effect is so great at high water with a S.W. wind, which continues for many days, though a calm may have succeeded, the violent action of the waters has not ceased, but break frightfully on Eddystone. An engraving of Mr. Winstanley’s light-house was published at the period of its erection, from which it appears to have been a stone tower of twelve sides, rising forty-four feet above the highest point of the rock, which, in the dimensions on which it was built, twenty-four feet in diameter, was ten feet lower on one side than it was upon the other; at the top was a balustrade and platform; upon this were erected eight pillars, which supported a dome of the same dimensions as the tower; from the top of which arose an octagon tower, of a diameter of fifteen feet, and seven in height. On the summit was placed the lantern, ten feet in diameter, and twelve in height: it had a gallery surrounding it, which gave access to the windows. The whole was surrounded by fencible iron-work. The entry was by a solid stone door at the bottom; the whole building was of the same material, except the aperture for the staircase. At the bottom was a room twelve feet high for a store-room; the next story was of the same height, which was the stateroom; and the third was of a similar height, which was the kitchen. Those compartments occupied the whole height to the platform. The dome above this contained the lodging-room; the octagon above it, the look-out.

The reason why it occupied so much time in building was, because the men could only work in the summer months. The first summer was occupied in making holes in the rock, and fastening irons to hold the future work. The second year was spent in erecting a solid pillar, of fourteen feet diameter, and one hundred and twelve feet high, for the future support of the building. The third year, it was augmented in diameter and increased in height. This building was eventually finished, within the time above-mentioned, at an enormous expense. It stood the opposition of the elements. The violence of the sea was so great, that Mr. Winstanley said it has been seen to rise upwards of one hundred feet above the vane, whilst the sides of the building were covered with surf as with a sheet, so that the whole house and lantern were occasionally under water. This edifice withstood the conflict of elements till 1703, when the architect, being at Plymouth, and desirous of visiting it, for the purpose of inspecting some repairs, went to it, but returned no more; for a storm arose, which left not a relic of it standing, except the iron work, which had been fixed in the rock. The Corporation of the Trinity House had then to erect another, for which purpose they employed a Mr. John Rudyard, who was a silk mercer, on Ludgate-hill. Mr. Rudyard’s mechanical ingenuity was said to have qualified him well for the undertaking. It appears that he erected a house made chiefly of wood, which presented many traits of his genius. It was a conical frustrum, one hundred and fifty-six feet in diameter at the base; its altitude sixty-two feet. At the top of the building was a balcony, railed round; in the centre of its area was the lantern. This building was made quite plain, excepting the well for the staircase, which was solid for thirty-two feet. In the centre a strong mast was erected. The building was admirably fixed to the rock, from the very peculiar manner of making the holes to hold iron cramps, they being made for the internal cavity to diverge on each side, by an extreme of one inch at the depth of sixteen inches. The cavity was first filled with tallow; the hot iron then dipped in the same substance, put in the rock, and eventually filled with pewter, which displaced the tallow, being heavier, the grease serving to protect the iron from the corrosive acidity of the salt water. In 1708, it was finished so far as to receive a temporary light. It stood forty-four years, and showed that it was liable to destruction from the very perishable nature of its materials. However, on the 2nd December, 1755, the upper part of it taking fire, burnt downwards to its entire consumption. The concern had been leased to a Captain Lovell; but at a later period his possessions were distributed among a number of people, when the care of rebuilding it was entrusted to Mr. Robert Weston, to whom Mr. John Smeaton was recommended by the President of the Royal Society, who appears to have been well qualified for the undertaking. He accordingly furnished a plan for, and superintended the building which now stands. Mr. Smeaton’s conjecture was quite different to that of the late projector; he conceived that nothing could withstand the action of the wind and water so well, and at the same time, prevent such accidents as the past, as could a building whose gravity should secure its most sure protection, He accordingly constructed his of the most massy stones, all dovetailed into each other, formed of Cornish-moor and Portland stone; all the joints breach each other, as the masons term it, or on each joint occurs the central stone of the next course. There are fourteen courses of these stones first laid in this manner, of a great thickness each course. On the 12th June, 1757, the first stone was laid in its place, each stone being pierced when it was laid, a strong oak pin was driven through to pin it fast to its place: the dovetails not fitting so close to each other, because it was necessary to leave some space for the cement, this pin was calculated to secure the stone till this could be applied and had fixed; the cement used was composed of Watchet lime and _puzzolana_, or Dutch terras, being made at the moment by mixing up in a pail, with water; this mixture was poured upon the work, and run into every cavity and crevice; this, however, was sometimes not exempt from the injury of the sea; whenever it was injured, the defect was supplied by having some oakum cut fine, and mixed with this cement, introduced into the joints; then they were secured with a coat of plaster of Paris, _pro tempore_, and this was never known to fail, if the work stood for one tide. In this manner the platform was erected, all of the most solid materials, and substantial workmanship.

On the 30th of September, 1758, the work having been continued from the 11th of the preceding May, had arrived at the store-room floor; here an iron chain was let into the stone, as follows: the recess being made and the chain being well oiled before insertion, the groove which received it was divided into four separate dams by clay; two kettles were used, to hold a sufficiency of melted lead, eleven hundred weight; whilst the lead was in a state of fusion, two men with ladles filled one quarter of the groove; as soon as it set, they removed one of the clay dams, and then filled the next quarter, pouring the liquid on the middle of the first quarter, it melted together into the second; the dam at the opposite end was now filled, and then the fourth; by this means the lead was associated into one solid mass. The centring for the floor was next set up, the outward stones being first set, and then the inner ones. Thus the base floor was finished. The men could work no longer than till the 7th of October that year. The winter was spent in preparing the iron, copper, and glass work for the lantern; and the spring in unsuccessful endeavours to discover the moorings for the vessel which attended the works, for the occasional retreat of the workmen. On the 5th of July the work was resumed: the stones for building had been hitherto raised from the boats by what are called shears, formed of two poles, with the lowermost ends extended to a sufficient width, whilst the upper ends met in a point; here was fastened tackle, pulleys, &c., to raise them to a sufficient height to be swung over the building; this course was now of necessity altered; a block with pulleys being suspended from the top, projected to a sufficient distance, supported by beams. After the base had been formed as described, a different mode of operation was necessary to complete the superstructure; the work being now advanced so high as to be out of the constant wash of the sea. Instead of grooves being formed to fasten the stones together, they were fixed by means of iron clamps and lead. The stones to complete the superstructure were landed, and first drawn up by machinery, called a _jack_, through the well, in the interior of the building, being a cavity for the staircase. The work now proceeded more rapidly, so that by the 26th of August, the stairs and all the masonry were finished: the iron frame for the lantern was next screwed together in its place, and the lantern soon completed. It should have been noticed, that after the first entry was closed, the shears were supported by a tackle called a _guy_, attached to the top of the shears, and hooked so far on the outside of the building; the stone being drawn up by a windlass, the guy was drawn in to swing the stone over the building. The balcony rails and the stone basement for the lantern having been completed, on the 17th of September the cupola was set up by a particular kind of shears constructed purposely, the guy in different places being fastened to booms projecting from the several windows of the upper rooms; the next day the ball was screwed on, and on the 11th of October, an electrical conductor was fixed, which finished the edifice. A light was then exhibited, which has continued to warn the mariner ever since. An ably constructed cornice throws the spray from off the building, so that it is often seen at Plymouth with the appearance of a white sheet, throwing itself to double the height of the building, which from low water mark to the apex of the ball is one hundred feet.

We have been thus minute, because this pharos is considered to be the best constructed of all our lighthouses.

ELECTRICITY.

Electricity was a property but imperfectly understood by the ancients; indeed, it has been said, they were entirely unacquainted with it. But we propose, shortly, to show the extent to which we are informed their sphere of knowledge extended. This much cannot be denied, that they were acquainted with the electrical properties of amber, of which fact we are informed by Pliny.

Even before Pliny, however, as early as the days of Thalis, who lived near six hundred years anterior to the Roman historian, the Miletine philosophers ascribed the attractive power of the magnet and of amber to animation by a vital principle. Our word “electricity” appears to be derived from the name the Latins gave to amber, _electrum_. It is also evident that they were acquainted with the shock of the torpedo; although they were ignorant, as are the moderns, of the concealed cause of this effect.

It has been asserted that the ancients knew how to collect the electrical fire in the atmosphere; and it is also said, that it was in an experiment of this nature that Tullus Hostilius lost his life. Etymologists have carried us still farther back, and assert that it was from the electrical property in the heavens that Jove obtained his surname of Jupiter _Eliaus_. This, however, may be only conjectural.

The first discoveries made of sufficient importance to demand the appellation of “scientific” in the science of electricity, were effected by Dr. W. Gilbert, the result of which he gave the world, in the year 1660, in a book then published, entitled “De Magneto,” and Dr. Gilbert was followed in his pursuits by that celebrated scientific character, the honourable and illustrious Boyle, and other men eminent for that species of information.

This science was successfully cultivated in the last century by many eminent philosophers, among whom we may mention Hawkesbee, Grey, Muschenbrook, Doctors Franklin and Priestly, Bishop Watson, Mr. Cavendish, and several other members of the Royal Society of England; whilst those worthy of the true philosophic character in France did not neglect its cultivation.

Many fatal accidents have resulted from experiments made by people ignorant of the science. On the 6th of August, 1753, at Petersburg, Professor Richmann lost his life by endeavouring to draw the electric fluid into his house.

Electricity, like many others of the arcana of nature, still retains almost as deeply shaded from human view as when its existence was first made known. Nature appears to have certain secret operations, which are not yet, perhaps, to be revealed.

ELECTRIC TELEGRAPH.

This is the most surprising invention of modern times, and of the greatest importance to a commercial people; by means of it intelligence is conveyed from one end of the kingdom to another, in the twinkling of an eye. A company was fully organised for the carrying out this invention, which commenced its operations in 1848, and established a system of no ordinary complication and extent. Their wires stretch from Glasgow on the north, to Dorchester, on the south, from the east coast, at Yarmouth, to the west, at Liverpool. These have brought upwards of one hundred and fifty towns into instant communication with each other. The wires set up for the use of the public alone are upwards of nine thousand eight hundred miles in length, and extend over a distance of two thousand and sixty miles, and, exclusive of those running underground, and through tunnels or rivers, are stretched on no fewer than sixty-one thousand eight hundred posts, varying from sixteen to thirty feet in height, and of an average square of eight inches, with an expensive apparatus of insulators and winders attached to each. As the most trifling derangement of the wires or apparatus will stop the communication, it is obvious that the utmost care and watchfulness is requisite to prevent and detect accidents. Accordingly, the whole distance is divided into districts, each district having a superintendent, and under him several inspectors, and a staff of workmen, batterymen, and mechanics, more or less numerous, according to the extent over which he presides.--When we consider these things, in conjunction with the central staff of engineers, secretaries, &c., at the head-establishment in London, a maximum charge of one penny per mile cannot be considered an exorbitant demand for the accommodation afforded to the public in keeping open so many receiving stations, and the maintenance of the expensive establishments. The telegraphic system is designed for important and urgent messages, and it may be safely averred that not one despatch in a hundred has been as yet forwarded by it, which has not been by many times worth more than the sum paid by the sender. A commercial house in Liverpool will scarcely grudge 8s. 6d. for a communication by which a necessary payment may be made, an important order given, or a profitable operation facilitated in London; and the message from Glasgow, which traverses a distance of five hundred and twenty miles in an instant, to summon a son from the metropolis, it may be, to the bedside of a dying parent, cannot be judged exorbitant at a charge of 14s., considerably less than one halfpenny per mile.

Messrs. Wilmer and Smith, of Liverpool, publishers of the “European Times,” have arranged the most admirable code of signals in the world; and by the use of forty-eight letters are capable of transmitting intelligence equal to half a column of an ordinary newspaper. The telegraphic company disapprove of this species of short-hand, and, therefore, charge for the forty-eight letters 13s. This Messrs. Wilmer and Smith consider excessive, as they have forwarded similar messages by telegraph, four thousand miles in America, for 8s., and from Philadelphia to New York for 1s. These gentlemen, therefore, consider they have cause to find fault with the company in reference to charges for communications in cipher.

STEAM-ENGINES.

The Steam-Engine is one of the most important of human discoveries, and is certainly one of those which afford the greatest portion of ease and advantage to the human species, as well in the operation of its cause, as in its ultimate effects. The most powerful of machines had its origin from the single idea of one individual of our own nation. It has been, from time to time, improved by different individuals, also natives of Britain, the precise period of which improvements can be traced, and their effects fortunately ascertained.

Although we should observe, that the first principle of this mechanical power was discovered by some of the ancient nations, many ages before that which gave the origin to the present practised invention, but from the state of information, it is conceived, to answer no purpose of utility. It may be said to have occurred in a small machine which the ancients called an _Æolipila_ (the bull of Æolus) consisting of a hollow ball of metal, with a slender neck, or pipe, also of metal, having a small orifice entering into the ball, by means of a screw; this pipe being taken out, the ball being filled with water, and the pipe again screwed in, the ball is heated--there issues from the orifice, when sufficiently hot, a vapour, with great violence and noise; care was required that this should not be by accident stopped, if it were, the machine would infallibly burst, and perhaps, to the danger of the lives of all in its vicinity, so immense is its power.

Another way of introducing the water was first to heat the ball when empty, and then suddenly to immerse it in water. Descartes, in particular, has used this instrument to account for the natural generation of winds. Chauvin thinks it might be employed instead of bellows, to blow a fire. It would admirably serve to fumigate a room, being filled with perfume instead of common water. It is said to have been applied to clear chimneys of their soot, a practice still alleged to be common in Italy. Dr. Plott, in his “History of Staffordshire,” records this singular custom, where the Æolipila is used to blow the fire. “The lord of the mannor of Essington is bound by his tenure to drive a goose, every New Year’s day, three times round the hall of the Lord of Hilton, while Jack of Hilton, a brazen Æolipila, blows the fire.” The last circumstance we shall mention of this instrument, has relation to an antique one, discovered whilst digging the Basingstoke canal, representing a grotesque metallic figure, in which the blast proceeded from the mouth. This figure is now in the possession of the Society of Antiquaries of London. In this instrument, the uncommon elastic force of steam was recognised before the suggestion of the Marquis of Worcester, which follows:

“In 1655, or subsequent thereto, the Marquis of Worcester published the earliest account of the application of this power for the purposes of utility, and suggested it as applicable to raising water. ‘Sixty-eight. An admirable and most forcible way to drive up water by fire; not by drawing or sucking it upwards, for that would be what the philosopher calleth it, _intra spherum actroctatis_, which is, but at such a distance. But this way has no bounder, if the vessel be strong enough; for I have taken a whole piece of cannon, whereof the end was burst, stopping and screwing up the broken end, as also the touch-hole; and making a constant fire under it, within twenty-four hours it burst and made a great crack: so that having a way to make my vessels, so that they are strengthened by the force within them, and the one to fill after the other, I have seen the water run like a constant fountain stream, forty feet high; one vessel of cold water being consumed, another begins to force and refill with cold water, and so successively; the fire being tended and kept constant, which the self-same person may likewise abundantly perform, in the interim between the necessity of turning the cocks.’”

The marquis’s ingenuity did not, it appears, meet with that attention which it deserved, from those to whom his communication was addressed. In the article of steam it has been since very much improved, and is acted upon for the most useful of purposes; also his ideas for short-hand telegraphs, floating baths, escutcheons for locks, moulds for candles, and a mode to disengage horses from a carriage, after they have taken fright; which, with several others, proclaim the originality and ingenuity of the mind of this nobleman--an honour which very few of the British nobility aspire to.

Since his time, another design upon the same principle has been projected by Captain Thomas Savery, a commissioner of sick and wounded, who in the year 1691 obtained a patent for “a new invention for raising water, and occasioning motion to all sorts of mill-work, by the impellant force of fire.” This patent bears date the 25th of July, sixteenth of William III., A. D. 1698. The patent states that the invention will be of great use for drawing of mines, serving towns with water, and working all sorts of mills. “Mr. Savery, June 14th, 1699, entertained the Royal Society with showing a model of his engine for raising water by help of fire, which he set to work before them; the experiment succeeded according to expectation.”

The above memoir is accompanied with a copperplate figure, with references by way of description; from whence it appears, that the engine then shown by Captain Savery was for raising water, not only by the expansive force of steam, like the Marquis of Worcester’s, but also by the condensation of steam, the water being raised by the pressure of a rarified atmosphere to a given height, by the expansive force of steam, in the same manner as the Marquis proposed. This action was performed alternately in two receivers, so that while the vacuum formed in one was drawing up water from the well, the pressure of steam in the other was forcing up water into the reservoir; but both receivers being supplied by one suction-pipe and one forcing-pipe, the engine could be made to keep a continual stream, so as to suffer very little interruption. This engine of Captain Savery’s displays much ingenuity, and is almost as perfect in its contrivance as the same engine has been made since his time. We regret, that without a figure we cannot supply a perfect description of it.

However, it appears that it was necessary to have two boilers, or vessels of copper, one large and the other smaller: those boilers have a gauge-pipe inserted into the smaller boiler, within about eight inches of its bottom, and about the centre of the side of the larger boiler; the small boiler must be quite full of water, and the larger one only about two-thirds full. The fire is then to be lighted beneath the larger boiler, to make the water boil, by which means the steam being confined, will be greatly compressed, and will, therefore, on opening a way for it to issue out (which is done by pushing the handle of a regulator from the operator), rush with great violence through a steam-pipe into a receiver, driving out all the air before it, sending it up into a force-pipe through a clack, as may be perceived from its noise; when the air is expelled, the receiver will be very much heated by the steam. When it is thoroughly emptied of atmospheric air, and grown very hot, which may be both seen and felt, then the handle of the regulator is to be drawn towards the operator, by which means the first steam-pipe will be stopped, so that no more steam can rise into the first receiver, by which means a second receiver will be filled in like manner. Whilst this is doing, some cold water must be poured on the first receiver, by which means the steam in it will be cooled, and thereby condensed into smaller room: consequently the pressure in the valve, or cock, at the bottom of the receiver--there being nothing to counterbalance the atmospheric pressure at the surface of the receiver in the inner part of the sucking-pipe, it will be pressed up into the receiver, driving up before it the valve at the bottom, which afterwards falling again, prevents the descent of the water that way. Then the first receiver being, at the same time, emptied of its air, push the handle of the regulator, and the steam which rises from the boiler will act upon the surface of the water contained in the first receiver, where the force or pressure on it still increasing its elasticity, till it exceeds the weight of a column of water in another receiving-pipe, then it will necessarily drive up through the passage into the force-pipe, and eventually discharge itself at the top of the machinery.

After the same manner, though alternately, is the first receiver filled and emptied of water, and by this means a regular stream kept continually running out of the top of a force-pipe, and so the water is raised very often from the bottom of a mine, to the place where it is meant to be discharged.

It should be added, that after the machine begins to work, and the water has risen into and filled the force-pipe, it fills also a little cistern, and by that means fills another pipe, called the condensing-pipe, which may be turned either way, over any of the receivers, when either is thoroughly heated by, the steam, to condense it within, thereby producing a vacuum, which absorbs the water out of the well into the receiver, on the principle of a syphon. Also a little above the cistern goes another pipe to convey the water from the force-pipe into the lesser boiler, for the purpose of replenishing the great boiler, when the water in it begins to be almost consumed. Whenever there is occasion for this, the cock is to be turned which communicates between the force-pipe and the lesser boiler, to close it effectually; at the same time having put a little fire beneath the small boiler, which will grow hot; its own steam, which has no vent to escape, pressing on its surface, will force the water up another pipe, through an aperture in the great boiler, and so long will it run, till the surface of the water gets so low as to be beneath the bottom of the pipe of communication--then the steam and water running together, will cause the valve (called a clack) to strike, which will intimate to the operator that it has discharged itself into the greater boiler, and carried in as much water as is then necessary; after which, by turning a cock, as much fresh water is let in as may be necessary; and then, by turning another cock, new fresh water is let out of a recipient into the less boiler as before; and thus the engine is supplied without fear of decay, or any delay in the operations; and proper attention in the workmen is only necessary to prevent disorder in a machine so expensive and complicated.

Also, to know when the great boiler wants replenishing, turn the gauge-cock; if water comes out, it does not need a supply; but if steam alone, then the want of water is certain. The like with the cock with which the lesser boiler is prepared for the same purpose, when the same state will be marked by like results. In working this engine, very little skill, and less labour is required: _Attention_ is the chief requisite; it is only to be injured by want of due care, extreme stupidity, or wilful neglect.

The engine described above, does not differ essentially from that first designed by the inventor, Captain Savery; the chief alteration which now occurs, is only in some few slight particulars. For example, the original engine had only one boiler, and there was no ready means for supplying it with water, to remedy the waste occasioned by evaporation of steam, without stopping the action of the engine, whenever the boiler was emptied to such a degree as to risk burning the vessel. After it was replenished the machine had to remain idle till the steam was raised, thus causing an immense loss of time; which is remedied by the application of a second boiler.

The description of the engine formerly mentioned is transcribed from Mr. Savery’s publication, “The Miner’s Friend,” and which had a subsidiary boiler, with water of a boiling heat, always ready to supply the large boiler; and the power of steam raised in it is employed to force the water into the larger boiler, to replace the waste occasioned by evaporation from that boiler; by this means the transposition of the feeding water is not only speedily performed, but being itself of a boiling heat, it is instantly ready to produce steam for carrying on the work. There is also one more grand improvement in the modern machine: the first engine was worked by four separate cocks, which the operator was compelled to turn separately at every change of stroke; if he turned them wrong, he was not only liable to damage the engine, but he prevented its effect, and, at the same time, lost a part of the operation: whereas, in the improved engine, the communications are made by a double sliding valve, or, as it has since been termed, regulator; that is, a brass plate, shaped like a fan, and moving on a centre within the boiler, so as to slide horizontally in contact with the under surface of the cover of the boiler, to which it is accurately fitted by grinding, and thus, at pleasure, opens or shuts the orifices, or entries, to the steam pipes of the two receivers alternately. This regulator acts with less friction than a cock of equal bore, and, by the motion of a single handle backwards, at once opens the proper steam pipe from one receiver, and closes that which belongs to the other receiver. Captain Savery, in his publication before noticed, describes the uses to which this machine may be applied, besides those before described, viz.--1, to serve water for turning all sorts of mills; 2, for supplying palaces, noblemen and gentlemen’s houses with water, and affording the means for extinguishing fires therein, by the water so raised; 3, the supplying cities and towns with water; 4, draining fens and marshes; 5, for ships; 6, for draining mines of water; and 7, for preventing damps in mines.

Dr. Desaguliers, we conceive, ungenerously attacked Captain Savery’s reputation, by alleging that this was not an original invention, and that he was indebted for the first idea to the previously mentioned plan of the Marquis of Worcester. Dr. Rees, with a generous liberality worthy his great critical discrimination, scientific skill, and general erudition, has, we think, ably defended the captain’s character, by proving his ideas to have originated with himself; we have only an opportunity to notice the most prominent features in this justification, where Dr. Rees thus expresses himself. “We know that the Marquis of Worcester gave no hint concerning the _contractibility or condensation of steam, upon which all the merit of the modern engine depends_. The Marquis of Worcester’s engine was actuated wholly by the elastic power of steam, which he either found out, or proved by the bursting of cannon in part filled with water; and not the least hint that steam so expanded, is capable of being so far contracted in an instant, as to leave the space it occupied in a vessel, and occasion, in a great measure, a vacuum.”

Subsequent to the Marquis of Worcester’s, and Captain Savery’s original ideas, and also, subsequent to the perfection the captain had brought his machine to, M. Amonton, a native of France, invented a machine which he called a fire-wheel; but it does not appear that it was ever brought to that perfection to be conducive to real utility, although it was certainly very ingenious.

Also, M. Papin, a native of Germany, made some pretensions to what he alleged was an invention of his own, only it happened to appear, unfortunately for his claim, that he was in London, and present at the time when Captain Savery exhibited the model of his steam-engine to the Royal Society. He made some unsuccessful experiments, by order of his patron, the Landgrave of Hesse, which sufficiently proved that, if he was the inventor, he did not understand the nature of his own machine.