To meet God in the immensity of his works, and trace him in the operations of his hand, gives expansion to intellect, opens new sources of enjoyment, and greatly exalts the character of man. The sacred writers conduct us to the forest, and, after selecting particular trees, press on our attention their emblematical uses.

Section III.—Minerals.

Gold — Silver — Platina — Mercury — Copper — Iron — Tin — Lead — Nickel — Zinc — Palladium — Bismuth — Antimony — Tellurium — Arsenic — Cobalt — Manganese — Tungsten — Molybdenum — Uranium — Titanium — Chromium — Columbium or Tantalium — Cerium — Oxmium — Rodium — Iridium — Religious Improvement.

Some parts of the earth’s surface are barren and unfruitful, yielding no pleasant herb for cattle, nor vegetable for the service of man. But the bowels of the earth in such places are commonly stored with rich mines, and useful minerals. Without these what could we do in the field, the house, the market, or crossing the seas? Surely, the infinitely wise Architect has not made any thing in vain! It is deserving of notice, says Mr. Parkes, that if minerals had been placed on the surface of the globe, they would have occupied the greatest part of the earth, and prevented its cultivation. Their being deposited below, is a proof of management and design worthy of that Being who could furnish so great a variety of this class of bodies.

There are twenty-seven distinct metals, which possess properties very different and distinct from each other. For a knowledge of most of these, we are indebted to the more perfect modes of analysis, which modern chemistry has afforded. The ancients were acquainted with only seven. The properties of these were tolerably well known to the early chemists, who acquired their knowledge from the alchemists. Metals are divided into two classes, by modern chemists. The one contains the malleable, and the other the brittle metals. This last class is sometimes subdivided into those which are easily, and those which are difficultly fused. The malleable metals are eleven, namely, Gold, Silver, Platina, Mercury, Copper, Iron, Tin, Lead, Nickel, Zinc, and Palladium. The brittle metals are Bismuth, Antimony, Tellurium, Arsenic, Cobalt, Manganese, Tungsten, Molybdenum, Uranium, Titanium, Chromium, Columbium or Tantalium, Cerium, Oxmium, Rodium, and Iridium.

Gold is the heaviest of all metals excepting platina; it is neither very elastic nor hard; but so malleable and ductile, that it may be drawn into very fine wire, or beaten into leaves so thin as to be carried away by the slightest wind. Dr. Black has calculated, that it would take fourteen millions of films of gold, such as is on some fine gilt wire, to make the thickness of one inch: whereas fourteen million leaves of common printing paper make near three quarters of a mile. According to Fourcroy, the ductility of gold is such, that one ounce of it is sufficient to gild a silver wire more than thirteen hundred miles long. Such is the tenacity of gold, that a wire 1-16th of an inch in diameter will support a weight of 500 pounds without breaking. Gold may be known from all other metals by its bright yellow color, and its weight. Its specific gravity is 19.3; when heavier, it must be combined with platina; when lighter, and of a deep yellow color, it is alloyed with copper; and if of a pale color, with silver.

Arabia had formerly its gold mines. The gold of Ophir, so often mentioned in Scripture, must be that which was procured in Arabia, on the coast of the Red Sea. We are assured by Sanchoniathon, and by Herodotus, quoted by Eusebius, that the Phœnicians carried on a considerable traffic in gold, even before the days of Job, who thus speaks of it, “Then shall thou lay up gold as dust, and the gold of Ophir as stones of the brooks.” Gold is found in Peru, as well as in several other parts of the world. It generally occurs in a metallic state, and most commonly in the form of grains. It frequently is met with in the ores of other metals, but is chiefly found in the warmer regions of the earth. It abounds in the sands of many African rivers, in South America, and in India. Several rivers in France contain gold in their sands. It has also been discovered in Hungary, Sweden, Norway and Ireland. Near Pamplona, in South America, single laborers have collected upwards of £200 worth of wash-gold in a day. In the province of Sonora, the Spaniards discovered a plain, fourteen leagues in extent, in which they found wash-gold at the depth of only 16 inches; the grains were of such a size that some of them weighed 72 ounces, and in such quantities, that in a short time, with a few laborers, they collected 1,000 marks, (equal in value to £31,219 10s. sterling,) even without taking time to wash the earth which had been dug. They found one grain which weighed 132 ounces; this is deposited in the royal cabinet at Madrid, and is worth £500.104 The native gold found in Ireland was in grains, from the smallest size to upwards of two ounces. Only two grains were found of greater weight, one of which weighed 5, and the other 22 ounces.105 Gold mines were formerly worked in Scotland; and indeed now, grains of this metal are often found in brooks after a great flood. It has been said, that at the nuptials of James V, covered dishes filled with coins of Scotch gold were presented to the guests by way of dessert. Standard gold of Great Britain is twenty-two parts pure gold, and two parts copper; it is therefore called gold of “twenty-two carots fine.” Some have thought that Moses made use of sulphuret of potass to render the calf of gold adored by the Israelites soluble in water. Stahl wrote a long dissertation to prove that this was the case.

Silver is a heavy, sonorous, brilliant, white metal; exceedingly ductile, and of great malleability and tenacity. It possesses these latter properties in so great a decree, that it may be beaten into leaves much thinner than any paper, or drawn into wire as fine as a hair without breaking. Fifty square inches of silver leaf weigh not more than a grain. The specific gravity of silver is 10.500. When perfectly pure, it is a very soft metal. To know when it is pure, heat it in a common fire, or in the flame of a candle: if it be alloyed, it will become tarnished; but if it be pure, it will remain perfectly white. Our standard silver is formed with fifteen parts pure silver, and one part copper.

Silver is found in various parts of the world in a metallic state; also in the states of a sulphuret, a salt, and an oxide. Native silver is found chiefly in the mines of Potosi. Sulphuret of silver occurs in the silver mines of Germany, Hungary, Saxony and Siberia. Oxides of silver are also common in some of the silver mines in Germany. Silver has lately been found in a copper-mine in Cornwall.106 Most of our lead mines also afford it, particularly some in Scotland. In the county of Antrim, in Ireland, there is a mine so rich, that every thirty pounds of lead ore is said to produce one pound of silver. By the silver which was produced from the lead mines in Cardiganshire, Sir Hugh Middleton is said to have cleared two thousand pounds a month, and that this enabled him to undertake the great work of bringing the New River from Ware to London.

Silver was used in commerce eleven hundred years before the foundation of Rome. Moses, says, “And Abraham weighed to Ephron the silver, which he had named in the audience of the sons of Heth, four hundred shekels of silver, current money with the merchant.” At this period silver was not coined, but being only in bars, or ingots, in commerce was always weighed. In the museum of the Academy of Sciences at St. Petersburgh, is a piece of native silver from China of such firmness, that coins have been struck from it without its having passed through the crucible.107

Platina, the heaviest of all metals, is nearly as white as silver, and difficultly fusible, though by great labor may be rendered malleable, so as to be wrought into utensils like other metals. It will resist the strongest heat of our fires without melting, and, like iron, is capable of being welded when properly heated. It is found in grains, in a metallic state, at St. Domingo: and also at Santa Fe, in Peru, in the language of whose inhabitants it means little silver. It has recently been discovered in an ore of silver found in Estremadura, existing in its metallic form. This metal was first introduced into England by Charles Wood, who brought it from Jamaica in the year 1741. It has been drawn into wire less than the two thousandth part of an inch in diameter. The specific gravity of hammered platina is 23.66, which is more than double that of lead.

Mercury, in the temperature of our atmosphere, is a fluid metal, having the appearance of melted silver: in this state it is neither ductile nor malleable; very volatile when heated; extremely divisible; and is the heaviest of all metals except platina and gold. We see it always in a fluid state, because it is so fusible that a small portion of caloric will keep it in a state of fluidity; but when submitted to a sufficient degree of cold, is similar to other metals, and may be beaten into plates. It has been determined, that at 39 degrees below zero of Fahrenheit’s thermometer is the point at which the congelation of mercury takes place. In the winter of 1799, Mr. Pepys froze 56 pounds of it into a solid and malleable mass. At Hudson’s Bay, frozen mercury has lately been reduced to sheets as thin as paper, by beating it upon an anvil that had previously been reduced to the same temperature. It is a substance so volatile that it may be distilled like water; and is sometimes purified in this way from mixture with other metals, being often adulterated with lead and bismuth. It is also so elastic when in a state of vapor, that it is capable of bursting the strongest vessels. According to Mr. Biddle, its specific gravity at 47 degrees above zero is 13.545; but when frozen into a solid at 40 below zero, 15.612.

This metal is brought to Europe from the East Indies and Peru; but is found in greater abundance at Almaden in Spain, where it is extracted from the ore by distillation. The quicksilver mine of Guanca Velica, in Peru, is 170 fathoms in circumference, and 480 deep. In this profound abyss are streets, squares, and a chapel where religious mysteries on all festival occasions are celebrated. Millions of flambeaux are continually burning to enlighten this subterranean abode. This mine generally affects those who work in it with convulsions. Notwithstanding this, the unfortunate victims of an insatiable avarice are crowded all together, and plunged naked into this abyss. Tyranny has invented this refinement in cruelty, to render it impossible for any thing to escape its restless vigilance.

Mercury is raised in such abundance in Spain, that in the year 1717 there remained above 1,200 tons of it in the magazines at Almaden, after the necessary quantity had been exported to Peru for the use of the silver mines there. The quicksilver mines of Idria, a town in the circle of Lower Austria, have been wrought constantly for 300 years, and are thought on the average to yield above 100 tons of quicksilver annually. Mercury is found also in Hungary and China; it occurs most commonly in argillaceous schistus, lime-stones, and sand-stones. It is likewise found in Sweden, amalgamated with silver, and frequently combined with sulphur. Running mercury is seen in globules, in some earths and stones in America, and is collected from the clefts of rocks. Cinnabar, or sulphuret of mercury, is also generally found in those countries which produce the fluid metal.108

Copper is of a red color, very sonorous and elastic, and the most ductile of all metals, except gold. A wire 1-10th of an inch will support near 300 pounds. Its specific gravity is 8.66. It will not burn so easily as iron; which is evident from its not striking fire by collision. Copper-mines have been worked in China, Japan, Sumatra, and in the north of Africa. Native copper is generally found in Siberia, Sweden, Hungary, and some parts of France. Copper is found in several parts of England and Wales, particularly in Cornwall, and the Isles of Man and Anglesea. The copper pyrites found in Cornwall are sulphuret of copper. Anglesea formerly yielded more than twenty thousand tons of copper annually: the vein of metal was originally more than seventy feet thick. Copper mines have not been worked in England above 160 years. Before that period, whenever the workmen met with copper ore in the tin mines of Cornwall, they threw it aside as useless, no English miner at that time knowing how to reduce it to a metallic state. To chemical science, therefore, we are indebted for such an ample supply of this valuable metal. It is asserted, that a large copper mine has been worked for some time in the state of New-Jersey in America, and that the ore raised there is brought to this country to be smelted. Native oxides of copper are found in Cornwall and in South America. Carbonate of copper occurs as a natural production in two varieties, called malachite and mountain green. Sulphate of copper, of a very rich quality, is also found in the state of Connecticut. The stream in its course destroys vegetation; and where it settles in places near the spring, large lumps of metallic salt are collected. Bishop Watson relates, that the waters which issue from the copper mines in the county of Wicklow, in Ireland, are so impregnated with sulphate of copper, that one of the workmen having accidentally left a shovel in this water, found it some weeks after so incrusted with copper, that he imagined it was changed into copper. The proprietors of the mines, in pursuance of this hint, made proper receptacles for the water, and now find these streams of as much interest to them as the mines. When miners wish to know whether an ore contains copper, they drop a little nitric acid upon it; after a short time they dip a feather into the acid, and then wipe it over the polished blade of a knife; and if there be the smallest quantity of copper in it, the copper will be precipitated on the knife.109 A mass of native copper has been found in a valley in the Brazils, containing 2,666 pounds weight. The description of it in the Memoirs of the Royal Academy of Sciences at Lisbon is said to be very interesting, as the largest specimen ever found before this weighs only ten pounds. In the museum of the Academy of Sciences at St. Petersburgh, is a piece of native malleable copper of extraordinary magnitude, found on the copper island lying to the east of Kamschatka.110 The Romans were acquainted with this metal; for the only money used by that people, till the 485th year of their city, was made of it, when silver began to be coined. In Sweden, houses are covered with copper.111

Iron is of a livid blueish color, and one of the hardest and most elastic of all metals. When dissolved, it has a nauseous styptic taste, and being strongly rubbed emits a peculiar smell. It is attracted by the magnet, and has the property of becoming itself magnetic. It is fused with great difficulty, but gives fire by collision with flint. An iron wire only one-tenth of an inch in diameter, will carry a weight of 450 pounds without breaking; and a wire of tempered steel, of the same size, will carry one of about 900 pounds. Iron becomes softer by heat, and has capability of being welded to another piece of the same metal so as to form one entire mass; and this may be done without melting either of the pieces. No other metal, except platina, possesses this singular properly, which renders it most suitable for every common purpose. Its specific gravity varies from 7.6 to 7.8.

This valuable metal is plentifully diffused throughout nature, pervading almost every thing, so as to be detected even in plants and animal fluids, and is the chief cause of color in earths and stones. It is found in large masses, and in various states, in the bowels of the earth. In the museum of the Academy of Sciences at Petersburgh is a mass of native iron twelve hundred pounds weight. In the northern parts of the world whole mountains are formed of iron ore, and many of these ores are magnetic. Of the English ores, the common Lancashire hematite produces the best iron. This metal is found in solution in many natural springs, and gives the character to all our chalybeate waters: besides which, there are some springs which contain iron in combination with sulphuric acid. These are called vitriolated waters. There are several in this land; but those at Chadwell near London, and at Swansea in Glamorganshire, are probably the most important.

As this metal possesses so many properties, exists in so many different states, and is capable of being applied to such a variety of excellent purposes, it is certainly the most useful of all the products of the mineral kingdom. It was used in the time of Moses, in whose writings Canaan is mentioned as “a land whose stones were iron.” The Greeks understood the method of tempering it. Homer, in the ninth book of his Odyssey, describes the fire-brand driven into the eye of Polyphemus, as hissing like hot iron immersed in water. The advantages which we derive from the magnetic property of iron are incalculable. To this we are indebted for the mariner’s compass, by which man is enabled to traverse the ocean, open a friendly or commercial intercourse with every quarter of the globe, and to steer his course with the utmost accuracy.

Iron may be moulded by the hammer into any form, and united into as many parts as the workman pleases, without rivets or solder. Were it not for this peculiar quality, many works of great importance could never have been executed. A most stupendous fabric, achieved by means of welded iron is the Chinese bridge of chains, hung over a dreadful precipice in the neighborhood of Kingtung, to connect two high mountains. The chains are twenty-one in number, stretched over the valley, and bound together by other cross chains, so as to form a perfect road from the summit of one immense mountain to that of the other.

Some idea of the extent and importance of the iron trade may be conceived from the following account, abridged from Malkin’s Scenery, &c., of South Wales. “Merthyr Tydvill was a very inconsiderable village till the year 1755, when the late Mr. Bacon obtained a lease of the iron and coal-mines of a district at least eight miles long, and four wide, for 99 years. Since then these mines have been leased by him to four distinct companies, and produce to the heirs of Mr. Bacon a clear annual income of ten thousand pounds. The part occupied by Mr. Crawshay contains now the largest set of iron works in the kingdom. He constantly employs more than two thousand workmen, and pays weekly for wages, coal, and other expenses of the works, twenty-five thousand pounds. The number of smelting furnaces belonging to the different companies at Merthyr is about sixteen. Around each of these furnaces are erected forges and rolling-mills, for converting pig into plate and bar-iron. These works have conferred so much importance on the neighborhood, that the obscure village of Merthyr Tydvill has become the largest town in Wales, and contains more than twelve thousand inhabitants.”

Tin is white, a little elastic, and so exceedingly soft and ductile, that it may be beaten out into leaves thinner than paper. It is much more combustible than many of the metals; and is soluble in all the mineral acids. Its specific gravity is 7.291, or about 516 pounds to the cubic foot. This metal is found in Germany, Saxony, South America, the East Indies, and in England, chiefly in Cornwall and Devonshire. It must have been known very early, as it is mentioned in the books of Moses. Homer in his Iliad mentions the use of tin.

Pliny says, that the Romans learned the method of tinning their culinary vessels from the Gauls. They used tin to alloy copper, for making those elastic plates which they employ in shooting darts from their warlike machines. The addition of tin to copper renders that metal more fluid, and disposes it to assume all the impressions of the mould. It was probably with a view to this, that it was used by the ancient Romans in their coinage. Many of the imperial large brass, as they are called, are found to consist of copper and tin alone. Antique coins frequently occur, made by forgers in the different reigns, in imitation of the silver currency, which contain a very large proportion of tin. There are coins of Nero which are of a most debased and brittle brass.

According to Aristotle, the tin mines of Cornwall were known and worked in his time. Diodorus Siculus, who wrote about forty years before the Christian era, gives an account of working these mines: he says, that their produce was conveyed to Gaul, and thence to different parts of Italy. The miners of Cornwall were so celebrated for their knowledge of working metals, that, about the middle of the seventeenth century, the renowned Becher, a physician of Spire, and tutor of Stahl, came over to this country on purpose to visit them; and it is reported of him, that, when he had seen them, he exclaimed, He who was a teacher at home, was a learner when he came there. About 3,000 tons of tin are furnished annually in Cornwall, two-fifths of which are usually exported to India by the East India Company. There are two kinds of tin known in commerce, namely, block tin, and grain tin. Block tin is procured from the common tin ore, and usually cast in blocks of about 320 pounds weight. It is taken to the proper offices to be assayed, where it receives the impression of a lion rampant, being the arms of the Duke of Cornwall, pays a duty of four shillings per hundred weight to the Duke, and then becomes legally salable. Grain tin is found in small particles, in what is called the stream tin ore. It appears to have been washed from its original bed in remote ages. This kind of tin owes its superiority, not only to the purity of the ore, but to the care with which it is washed and refined.

Lead is of a blueish white color, scarcely sonorous, unelastic, and, being the softest of all metals, yields readily to the hammer. It generally contains a small quantity of silver. An alloy of this metal with tin forms pewter, and in different proportions soft solder. Its specific gravity is 11.35. Lead ore is very abundant in Scotland, the western parts of Northumberland and Durham, Derbyshire, and many other parts of the world. The lead found in these counties occurs on the estates of Colonel Beaumont, and of those of the late Lord Derwentwater: the last of these were forfeited to Government; and are now in the possession of Greenwich Hospital. Lead was known in the time of Moses, and was in common use among the ancients. The Romans sheathed the bottoms of their ships with it, fastened by nails made with bronze. During the first century, at Rome, it was twenty-four times the price it is now in Europe; whereas tin was only eight times its present price.

Nickel is white, ductile and malleable, but of difficult fusion. It is attracted by the magnet, and has itself the property of attracting iron: but as the nickel of commerce always contains iron, this may disguise its properties, and prevent its nature being exactly known, Richter, in his Annales de Chimie, asserts, that this metal, in its pure state, is nearly as brilliant as silver, and more attractable by the loadstone than iron; that it is not liable to be altered by the atmosphere; and that its specific gravity when forged is 8.666. The ore of nickel is procured from various parts of Germany, and is often found with cobalt. It is chiefly used in China; and it is said, that the manufacturers of Birmingham combine it with iron, and melt it with brass, with great advantage.

Zinc possesses but a small degree of malleability and ductility, except under certain circumstances. When broken, it appears of a shining blueish white; and when exposed to the air, becomes covered with a pellicle which reflects various colors. If beaten out into thin leaves, it will take fire from the flame of a common taper. Its filings are mixed with gunpowder, to produce those brilliant stars and spangles which are seen in the best artificial fire-works. It is also one of the metals employed to form Galvanic batteries. It is the most combustible metal we have. It will decompose water without the assistance of heat. Next to manganese, it has the strongest affinity for oxygen of all the metals. Its specific gravity is 6.861. Its nature is such, that it seems to form the link between brittle and malleable metals. Some mineralogists consider zinc to be the most abundant metal in nature, excepting iron. Calamine, or lapis calaminaris, which is a native oxide of zinc, combined with carbonic acid, is found both in masses and in a crystallized state, and is generally combined with a large portion of silex. Zinc is also found in an ore called blend, in which state it is mineralized by sulphur. The miners call it Black Jack—a mineral employed till lately in Wales for mending the roads. Zinc is generally called by our artists spelter; and in England and elsewhere it is extracted from calamine, and other ores, by distillation. This metal abounds in China, where it is used for current coin, and for that purpose is employed in the utmost purity. These coins have frequently Tartar characters on one side, and Chinese on the other. They have generally a square hole in the centre, that they may be carried on strings, and more readily counted.

Antimony is of a dusky white color, brilliant, brittle, and destitute of ductility. Though seemingly hard, it may be cut with a knife. Its specific gravity, according to Bergman, is 6.86. It is procured from an ore which is found chiefly in Hungary and Norway. Native antimony, alloyed with a small portion of silver and iron, has been found in Sweden. And it is said, that it has been found in the state of Connecticut, in America, nearly in a pure metallic form. There are five distinct ores of antimony, but the grey is the only one found in sufficient quantity for the manufacturer; it is a sulphuret of antimony. Perhaps we have no metal more valuable as a medicine than this, or one which is applied in such various ways.

Bismuth is of a yellowish white color, lamellated texture, and moderately hard, but not malleable. It is so brittle that it breaks readily under the hammer, and may be reduced to powder. It has the singular property of expanding as it cools. Hence, probably, its use in the metallic composition for printers’ types; as from this expansive property are obtained the most perfect impressions of the moulds in which the letters are cast. In manufactories this metal is known to the workmen by the name of tin glass. It is one of the metals which will inflame when suspended in oxymuriatic acid gas. It is generally found with cobalt in the cobaltic ores of Saxony and England. Native bismuth, and sulphuret of bismuth, are found on the continent; and a sulphuret of bismuth has been discovered in Cornwall; but this is not an abundant metal. If 8 parts of bismuth, 5 of lead, and 3 of tin, be melted together, the mixed metal will fuse at a heat no greater than 212°. Tea-spoons made of this alloy are sold in London, to surprise those who are unacquainted with their nature. They have the appearance of common tea-spoons, but melt as soon as they are put into hot tea.

Arsenic, when reduced to its pure metallic state, is a friable brilliant metal, of a blueish white color, easily tarnishing, or oxidizing, by exposure to the air. In all its states it is extremely poisonous. It may be known by the smell of garlic, and by the white fumes which it exhales when thrown upon a piece of red-hot coal. Its specific gravity is 8.310. It is found in Bohemia, Hungary, Saxony, and other places on the continent; and in combination with acids, sulphur, or oxygen. The arsenic of commerce is prepared in Saxony, in the operation of roasting the cobalt ores for the manufacture of zaffre. The reverberatory furnace in which the ores are roasted terminates in a long horizontal chimney; and in this chimney the arsenical vapors are condensed, forming a crust, which at stated times is cleared off by criminals, who are condemned to this work.

Cobalt is a whitish-grey, brittle metal, nearly resembling fine hardened steel; is difficult of fusion, but obedient to the magnet. According to Bergman, its specific gravity is about 7.700; though Tassaret makes it 8.538. Formerly all our cobalt came from Saxony. The cobalt ores of Hesse produce a nett profit of £14,000 a year, as stated in Born’s Travels; though once they were used for no other purpose than to repair the roads. But now cobalt is found abundantly in the Mendip hills in Somersetshire, and in a mine near Penzance in Cornwall. Zaffre is now made from the cobalt ores found in these hills. Had it not been for the rapid promulgation of chemical science in these kingdoms, this important metal might have lain in the bowels of the earth undiscovered for ages yet to come. Formerly miners not only threw cobalt aside as useless, but they considered it so troublesome when they found it among other ores, that, as stated in Beckmann’s History of Inventions, a prayer was used in the German church, that God would preserve miners from cobalt and from spirits. It is now very valuable to the manufacturers of porcelain.

Manganese is of a dark grey color, brilliant, very brittle, of considerable hardness, and difficult fusibility. Its specific gravity has been estimated by Bergman at 6.850, and by Hielm 7.00. It is never found native. It was first procured in its pure metallic form by Kaim and Gahn between 1770 and 1775. It abounds in America, and in various parts of the continent. The manganese which is used in England, is obtained in a state of black oxide from Somersetshire and Devon. It is found either in the state of an oxide or a salt. But the discovery of mines of it in this country is a new acquisition, owing to the spirit of chemical research. Dr. William Dyce, of Aberdeen, has lately communicated to the Society for the Promotion of Arts, &c., the discovery of a mine of great extent, and very fine quality, in the vicinity of that town: for which the gold medal of the Society was sent him. Professor Beattie, of the same place, has also discovered manganese in his neighborhood, on the river Don, of good quality. Scheele discovered this metal in the ashes of burnt vegetables. Proust has lately announced the discovery of a native sulphuret of manganese. That from the Bristol and the Mendip hills generally contains lead.

Tungsten is a heavy metal, but its properties are not much known. It is procured from a mineral found in Sweden, and from an ore called wolfram, found in Cornwall, Germany, &c. It has been used in France for making vegetable lakes; but is not used here. Though it has been recommended as a proper basis for colors, it shows in some instances a strange fugacious disposition. Its specific gravity is 17.60.

The same may be said of the other metals, their properties not being much known. Molybdenum was first procured in a metallic state by Hielm, in the year 1782; and, it is believed, has been employed in some processes of dyeing in Germany. As the ore may be had in great plenty, it will probably, some time hence, come into general use here. At present it is not used in any of the arts. Its specific gravity is 8.61. Uranium was discovered by Klaproth in 1789, in a mineral called pechblend; and has since been found combined with carbonic acid, in the common green mica. Titanium was first noticed in the year 1781, by Mr. Macgregor, in a greyish black sand, found in the vale of Menachan in Cornwall; but has since been discovered by Klaproth in several other minerals. An ore of it occurs in Transylvania, which very much resembles yellow sand. This metal has been used in France for painting porcelain. Tellurium was discovered by Klaproth in the year 1798, in a particular kind of gold ore. It has hitherto been found in quantities too small to allow of its being employed in the arts. Its specific gravity is only 6.115. Chromium received its name from a property it has of imparting a lively color to a variety of other bodies. The emerald is colored by an oxide of this metal. Columbium was discovered in a mineral sent from Massachusetts in North America. Tantalium was found in an ore from Swedish Lapland: but Dr. Woollaston has lately discovered that this and columbium are identically the same metal. Cerium had not been seen in a metallic form till Sir Humphrey Davy procured it from some oxide discovered by Hissinger and Berzelius in 1804. Its scarcity will prevent its being applied to any useful purpose.

The metals are simple substances, distinguishable from all other bodies by their lustre, great specific gravity, perfect opacity, and superior power of conducting electricity. They are the great agents by which we are enabled to explore the bowels of the earth, and examine the recesses of nature. Their uses are so multiplied, that they are become of prime importance in every occupation of life.

The reason why one metal possesses such opposite and specific differences from those of another, is not to be attributed to chance, but must certainly be the effect of consummate wisdom and contrivance. These metals differ so much from each other in their degrees of hardness, lustre, color, elasticity, fusibility, weight, malleability, ductility, and tenacity, that the Author of nature appears to have had in view all the necessities of man coming within the range of their operation.112

[It is now generally admitted that there are forty distinct metals.

Some of these metals are the bases of the alkalis, alkaline earths, and earths. And as this class of metals is but little known to the great mass of readers, some remarks will be acceptable: they are recommended to his special attention, as they form the base of the only satisfactory theory of volcanos and earthquakes. The number of metals in this class are twelve.

1. The bases of the three alkalis, potash, soda, and lithia.

The base of potash is potasium. This metal was discovered in 1807 by Sir H. Davy. Its texture is crystalline; color and lustre similar to mercury. It is solid at the ordinary temperature of the atmosphere; somewhat fluid at 70°, melts at 150°. Its affinity for oxygen is so great that it oxidizes rapidly in the air; and decomposes water instantly upon contact, emitting heat, flame, and light, as it swims on the surface of the water, being the lighter substance. In these cases it oxidizes and becomes potash, by abstracting oxygen from the air and water.

The base of soda is sodium. This metal was discovered by the same chemist the same year. It has the strong metallic lustre of silver. It fuses at 200°, and evaporates at a full red heat. It decomposes both air and water, but not so rapidly as potasium. When thrown on water it effervesces strongly; and inflames with light, when thrown on boiling water. In these cases soda results, which is the oxide of sodium. This metal is the base of common salt.

The base of lithia is lithium. This metal was discovered in Sweden in 1818, by Arfwedson. It is of a white color, like sodium; but oxidizes so rapidly as not to be kept in its pure metallic state. Its peculiar properties are, therefore, not so certainly known. Its alkaline quality is well ascertained, when in combination with oxygen, in which form it commonly appears.

2. The bases of the four alkaline earths, baryta, strontia, lime and magnesia.

The base of baryta is barium. This metal was discovered by Sir H. Davy, in 1808. It is of a dark gray color, very heavy, and attracts oxygen very strongly from the air, and from water, with effervescence, caused by the escape of hydrogen gas, and thus becomes an oxide which is the pure earth baryta, of a white color, and very heavy. Its intimate properties are not yet well known.

The base of strontia, is strontium. This metal is very much like barium, in color, weight, and power of decomposing air and water, and thus becoming an oxide, which is the earth strontia. Yet it is satisfactorily distinguished from barium.

The base of lime is calcium. This metal was satisfactorily obtained first by Sir H. Davy. It is of a whiter color than the two last mentioned metals; and like them decomposes the air and water, and thus becomes lime, which is an oxide of calcium. The base of common limestone is, of course, a metal.

The base of magnesia is magnesium. This metal was discovered by Sir H. Davy, but in very small quantities; sufficient, however, to determine its strong affinity for oxygen, so as to decompose water, and thus oxidize, and become the earth magnesia, which is a metallic oxide. The base of common magnesia is, of course, a metal.

3. The bases of the five earths, alumina, glucina, yttria, zirconia, and silica.

The base of alumina is aluminium. The existence of this metal was pretty satisfactorily ascertained by Sir H. Davy, and subsequently established by Wöhler. It is very difficult to obtain it, as the preparation is attended with intense heat and light. When obtained it is generally in small scales of a metallic lustre. It requires a great heat to fuse it; and when heated to redness in the open air, it burns with a bright light, and the product is an oxide of aluminium, which is pure clay, of a white color, and quite hard.

This oxide, or pure clay, is very abundant in the composition of the earth, though generally very much adulterated. It is found in all countries and used for making bricks, porcelain ware, pipes, &c. When pure it sometimes crystallizes. Hence it is capable of forming some of the most beautiful gems: as the sapphire and ruby, which are pure crystallized clay. Clay, then, has a metallic base.

The base of glucina, is glucinium. Glucina was first discovered by Vauquelin in 1798, and by analogy its base was supposed to be metallic, which has since been confirmed by Dr. Wöhler, who has obtained the base in the form of a metal. An. de ch. et de ph. Sept. 1828, as quoted by Dr. Bache, Turner’s Chem. p. 303.

The base of yttria is yttrium. This metal was obtained in a separate state by Dr. Wöhler, (See last quoted authority,) though its existence was inferred by Godolin who discovered the earth which is an oxide of this metal.

The base of zirconia is zirconium. The earth was discovered by Klaproth in 1789, and its metallic base clearly established by Berzelius 1824.

The base of silica is silicium. There exists some doubts among chemists whether this base is indeed a metal; but there is no doubt but that it is combustible, and that the earth silica, (or silex,) is an oxide. From analogy it would be inferred this base is metallic, and the evidence preponderates on this side. This oxide, or earth, is very abundant. It is more commonly called silex. It is the base of the whole class of primitive rocks, and almost altogether constitutes quartz, flint, &c.

The reader is now desired to recollect that this class of metals constitutes the bases of the alkalis, and earths; which are simply metallic oxides or a combination of oxygen with the metals. Recollect also that all these metals are inflammable, and some of them simply upon exposure to air and water. Now as the earths at the surface of our globe are the results of chemical action, in which the oxygen combined with the metals, it is beyond a doubt that these substances were created in their elementary and uncombined state; and that the act of combining would produce an inconceivable amount of heat, so as to fuse completely the whole mass of our earth; and in this state of fusion the oxides would commence forming at the surface chiefly; and thus by oxidizing the metals would form the earths, rocks, &c., which constitute, principally, the crust of our globe. When this crust became sufficiently thick it would protect the interior parts of the earth from oxidation, by preventing the access of air and water; and they would of course remain in a pure metallic state. But, (as is most probable,) if the materials, being promiscuously mixed throughout the mass at the commencement of the chemical action, should oxidize throughout, then the indurating of the crust, by cooling, would inclose the interior parts in a state of fusion, and in that state they remain to the present time. Nor is this astonishing when we recollect the earths are almost perfect non-conductors of caloric: of course it could not escape at all through the crust of the earth, formed of many strata of earths, in the shape of rocks, which, taken together, may be about eight miles thick.

If, by any concussion, or by percolation, water, or air should reach these metals in the interior, or these fused masses of matter, the consequence would be decomposition, and the production of a great amount of gas, and heat, which operating conjointly, first produce earthquakes by struggling to escape from the caverns in which they are generated; and when they find a passage, they would break forth into volcanos. This is the only true and satisfactory theory of earthquakes and volcanos.

It may be added, that this action would naturally bring to its aid the astonishing powers of electricity and galvanism.

The forty metals mentioned above, may be classed scientifically into two classes.

1. The bases of the alkalis, alkaline earths, and earths. These are twelve: potasium, sodium, and lithium; bases of the alkalis—barium, strontium, calcium, and magnesia; bases of the alkaline earths—aluminium, glucinium, yttrium, zirconium, and silicium; bases of the earths.

2. Metals, the oxides of which are neither alkalis, or earths. These are twenty-eight in number, and may be set down in the following order: gold, silver, iron, copper, mercury, lead, tin, antimony, zinc, bismuth, arsenic, cobalt, platinum, nickel, manganese, tungsten, tellurium, molybdenum, uranium, titanium, chromium, columbium, palladium, rhodium, iridium, osmium, cereum, and cadmium.

Not only the first class of metals are combustible, but the last also. All the metals are now well known to be combustible bodies, and may be made to burn as really as wood.]

Gems are of a higher order than metals, of a more refined nature, and consist of two classes, the pellucid and semi-pellucid. Those of the first class are bright, elegant, and beautiful fossils, naturally and essentially compound, ever found in small detached masses, extremely hard, and of great lustre. Those composing the second class are stones naturally and essentially compound, not inflammable nor soluble in water, found in detached masses, and composed of crystalline matter debased by earth: however, they are but slightly debased, are of great beauty and brightness, of a moderate degree of transparency, and usually found in small masses.

The knowledge of the gems depends principally on observing their hardness and color. Their hardness is commonly allowed to stand in the following order: the diamond, ruby, sapphire, jacinth, emerald, amethyst, garnet, carneol, chalcedony, onyx, jasper, agate, porphyry, and marble. This difference, however, is not regular and constant, but frequently varies. In point of color, the diamond is valued for its transparency, the ruby for its deep red, the sapphire for its blue, the emerald for its green, the jacinth for its orange, the amethyst for its purple, the carneol for its carnation, the onyx for its tawny, the jasper, agate, and porphyry, for their vermillion, green, and variegated colors, and the garnet for its transparent blood-red.

There is not a unity of opinion concerning the cause of this difference. “Their colors,” says Cronstedt, “are commonly supposed to depend upon metallic vapors; but may they not more justly be supposed to arise from a phlogiston united with a metallic or some other earth? because we find that metallic earths which are perfectly well calcined give no color to any glass; and that the manganese, on the other hand, gives more color than can be ascribed to the small quantity of metal which is to be extracted from it.” M. Magellan is of opinion, that their color is owing chiefly to the mixture of iron which enters their composition; but approves the sentiment of Cronstedt, that phlogiston has a share in their production, it being well known that the calces of iron when dephlogisticated, produce the red and yellow colors of marble, and when phlogisticated to a certain degree produce the blue or green colors.

With regard to the texture of gems, M. Magellan observes, that all of them are foliated or laminated, and of various degrees of hardness. Whenever the edges of these laminæ are sensible to the eye, they have a fibrous appearance, and reflect various shades of color, which change successively according to their angular position to the eye. These are called by the French chatorantes; and what is a blemish in their transparency, often enhances their value on account of their scarcity. But when the substance of a gem is composed of a broken texture, consisting of various sets of laminæ differently inclined to each other, it emits at the same time various irradiations of different colors, which succeed one another according to their angle of position. This kind of gems has obtained the name of opals, which are valued in proportion to the brilliancy, beauty, and variety of their colors. Their crystallization, no doubt, depends on the same cause which produces that of salts, earths, and metals: but as to the particular configuration of each species of gems, we can hardly depend upon any individual form as a criterion to ascertain each kind; and when we have attended with the utmost care to all that has been written on the subject, we are at last obliged to appeal to chemical analysis, because it very often assumes various forms.113

The rich treasures of the earth are within it, observes a worthy author, so that they cannot be discovered and brought to the surface without the labor of man; yet they are not placed so deep, as to render his exertion ineffectual. Thus nothing but what is comparatively worthless is to be found by the indolent on the surface of life. Every thing valuable must be obtained by diligent research and sedulous effort. All wisdom, science, art and experience, are hidden at a proper depth for the exercise of intellect, and they who bend their attention to any of these objects shall not be disappointed in their pursuit.

The treasures of wisdom, which are displayed in the redemption of mankind by Jesus Christ, and recorded in the Divine Oracles, do not lie upon the surface of the letter, for every superficial reader to observe them: therefore our Lord says, “Search the Scriptures.” The word ερευνατε, compounded of ερεω, I seek, and ευνη, a bed, is, says St. Chrysostom, “a metaphor taken from those who dig deep and search for metals in the bowels of the earth. They look for the bed where the metal lies, and break every clod, and sift and examine the whole, in order to discover the ore.” In Leigh’s Critica Sacra, we meet with these observations, illustrative of the Greek word—“Search; that is, shake and sift them, as the word signifies: search narrowly, till the true force and meaning of every sentence, yea, of every word and syllable, nay, of every letter and yod therein, be known and understood. Confer place with place; the scope of one place with that of another; things going before with things coming after: compare word with word, letter with letter, and search it thoroughly.”

The Holy Scriptures contain the most invaluable treasures, a complete collection of doctrines, precepts, and promises, necessary to everlasting happiness. In this respect they have a peculiar advantage above all the writings of the most distinguished philosophers in the heathen world. The Bible presents an exact model of religion, for the instruction and common benefit of mankind. Here we have, in a narrow compass, all the things necessary to be known, believed, and practised, in order to our salvation; for it is, “a lamp to our feet, and a light to our path.” We are taught the knowledge of the only living and true God, his spiritual nature, adorable perfections, and endearing relations to his rational creatures: so that the meanest Christian who can read, may arrive at more true and just notions of him, than the wisest heathen sages could attain, who as the Apostle intimates, did only grope after him in the dark.—We are informed how Adam was created, how he fell, and what is the consequence of his transgression to all his posterity: the most celebrated heathens were not able to account for the origin of moral evil, as affecting the human race. The glorious plan of redemption by Jesus Christ is set before us, in its commencement, progress, and completion; which is the highest display of the moral perfections of God, and attended with the most beneficial advantages to man.—The rules of duty, all the agenda of religion, or things to be done, are plainly stated, and properly enforced. Promises, containing pardon, adoption, sanctification, and eternal life, are every where interspersed, and are “yea, and amen, in Christ.”

Our obligation to search the Scriptures, and by that means acquaint ourselves with their valuable contents, appears from the necessity and design of committing them to writing. St. Paul says, “All scripture is given by inspiration of God, and is profitable for doctrine, for reproof, for correction, for instruction in righteousness: that the man of God may be perfect, thoroughly furnished unto all good works.” But how can they contribute to these important ends without being read? What effect could the mere writing of them have on mankind, to inform the judgment and regulate the life? How could Christian motives have proper influence, if the Sacred Volume were neglected? Is it not an insult to common sense, to assert that the Scriptures were written for our instruction and admonition, but it is not necessary to peruse them to learn what they teach? To have a Bible, and not to read it, for direction in the way of truth and holiness, would not be attended with any peculiar advantage. Precious metals, deposited in the earth, must be procured to be rendered beneficial. The Holy Scriptures contain the revelation of God to mankind, declare his will with certainty, and are the prescribed means of salvation: the Apostle says, “they are able to make us wise unto salvation, through faith that is in Christ Jesus.”

CHAPTER V.
FOURTH DAY.

Section I.—The Sun.

Signs — Names — Nature — Motions — Form — Magnitude — Distance — Suspension — Idolatrous worship of the Sun — The Sun an Emblem of Christ.

On the fourth day, “God said, Let there be lights in the firmament of the heaven to divide the day from the night, and let them be for signs, and for seasons, and for days, and years: and let them be for lights in the firmament of the heaven to give light upon the earth: and it was so. And God made two great lights; the greater light to rule the day, and the lesser light to rule the night: he made the stars also. And God set them in the firmament of the heaven, to give light upon the earth, and to rule over the day and over the night, and to divide the light from the darkness.” The light which had hitherto been scattered and confused, was now collected and formed into several luminaries, and so rendered more glorious and of greater utility.

A sensible and pious author observes, that not only the two great lights, which were made after a special manner to rule the day and the night, but, in general, all the lights in the firmament of the heaven, are said to be for signs and for seasons; or, as some render the words, “for signs of the seasons.” And indeed this seems to be the meaning of the inspired writer. As for the manner of expression, “for signs and for seasons,” it is very common in the Hebrew, as well as in many other languages, and is a figurative way of speech, expressing those things disjunctively, which must by the understanding be joined together. First, these lights are said to be for signs, and then the things are mentioned which they are to signify, namely, the seasons, the days, and the years: whereas, if we understand the word signs in an indefinite sense, and not confined to what follows, we are through the whole text left in great uncertainty; seeing that there are signs appointed in the heaven for some purpose or other, but not knowing for what. Besides, if we must take all the parts of the text disjunctively, then “the lights in the firmament” must be taken for seasons, and for days, and for years, as well as for signs. But we know, that the celestial bodies are not themselves seasons, and days, and years, but only signs of them, by such particular motions and aspects, as God, according to the laws of nature, has ordained them. Neither can I see reason to believe, that every motion or position of the heavenly bodies has a special signification in it: though serving in general to display the wisdom and power of God, in their regular courses. The sun, indeed, which is called the greater light, is said to rule the day, as it is by the appearance of his light, increasing and decreasing, that we measure the length of the day; and the moon likewise to rule the night, partly on the like account. Thus likewise the sun’s course (if we may so call it) is a determining sign of the beginning and ending of the year, and of its various seasons. And in general, the sun, the moon, and the other lights, are necessary signs of the seasons of sowing, reaping, planting, and are useful in navigation, as well as other arts.

Costard, in his History of Astronomy, makes some critical remarks on the name of this greater light. He says, The sun is, by the Greeks, called Ἡλιος: which is nothing more than the Hebrew word אל El, modelled after the Greek manner of pronunciation, and signifies Lord; the first idolatrous worship being paid to this planet. In the Hebrew language it is called שמש Shemesh, and in the Chaldee שמשא Shimsha, from שמש Shamesh, to minister, on account of its administering light and heat to this world. From this property of communicating heat, it is also called המה Hammah. By the Phœnician idolaters it seems to have been called בעל Baal, or בעל שמים Baal-Shamim, the Lord of Heaven. And on account of the supposed swiftness of its diurnal motion from east to west, it had a chariot dedicated to it at Sidon, an ancient town of Phœnicia. Such a chariot is still seen on the coins of that place. This superstition was likewise imitated by the idolatrous Jews: for we read of the horses which the kings of Judah had given, or dedicated, to the sun. By the Chaldeans it seems to have been called בל Bel, and by the Assyrians פל Pul; and, with the addition, sometimes of אב ab, or אף ap, i.e. father, אף-פל Ap-Pul, or Father-Lord; from whence the Greeks formed their Απολλων, another name given by them to the sun. The name of this luminary, among the Romans, was sol; given more probably, on account of his scorching heat in the summer, or from his determining the length of the year by his course, than because he appeared solus, alone, according to the derivation given by Macrobius.

The nature of the sun is a subject which has not only excited the most diligent inquiry among men of scientific knowledge, but the opinions concerning it have passed through a variety of vicissitudes. The sun being evidently the source of light and heat, was by the ancients considered to be a globe of fire. But Dr. Herschell’s discoveries, by means of his immensely large telescopes, tend to prove, that what we call the sun is only the atmosphere of that luminary: “that this atmosphere consists of various elastic fluids, which are more or less transparent; that as the clouds surrounding our earth are probably decompositions of some of the elastic fluids belonging to the atmosphere itself, so we may suppose that in the vast atmosphere of the sun similar decompositions may take place, but with this difference, that the decompositions of the elastic fluids of the sun are of a phosphoric nature, and are attended by lucid appearances, by giving out light.” The body of the sun this celebrated astronomer considers as hidden generally from us, by means of this luminous atmosphere; that what are called maculæ, or spots on the sun, are real openings in this atmosphere, through which the opaque body of the sun becomes visible; that this atmosphere itself is not fiery nor hot, but is the instrument which God designed to act on the caloric or latent heat; and that heat is only produced by the solar light acting on and combining with the caloric or matter of fire contained in the air, and other substances which are heated by it.

This indefatigable investigator of the heavenly phenomena shows, by many substantial proofs, drawn from natural philosophy, that heat is produced by the sun’s rays only when they act on a calorific medium; and that they cause the production of heat by uniting with the matter of fire which is contained in the substances that are heated,—as the collision of flint and steel will inflame a magazine of gunpowder, by uniting with its latent fire, and bring the whole into action. This point is capable of a very clear elucidation. “On the tops of mountains, and at heights to which the clouds seldom reach to shelter them from the direct rays of the sun, we always find regions of ice and snow. Now if the sun’s rays themselves conveyed all the heat we find on the earth, it would of course be hottest in situations similar to the tops of mountains, where their course is least interrupted. But all those who have ascended in balloons confirm the coldness of the upper regions of the atmosphere; and, therefore, since even on the earth the heat of the situation depends on the facility with which the medium yields to the impression of the sun’s rays, we have only to admit, that, on the sun itself, the fluids composing its atmosphere, and the matter on its surface, are of such a nature as not to be capable of any excessive heat from its own rays. It is also a well known fact, that the focus of the largest burning lens thrown into the air, will occasion no heat in the place where it has been kept for a considerable time, although its powers of exciting heat, when proper bodies are exposed to it, should be sufficient to melt or fuse the most refractory metals.” That the sun is a luminous, and not an igneous body, has met with the general consent of modern philosophers; an opinion to which every new discovery in philosophy gives additional support.

The telescope, said to have been invented by the children of a spectacle-maker at Middleburgh, in the year 1590, but first brought to such a degree of perfection by Galileo as to make any considerable discoveries in the celestial regions, has led to the most important results in the science of astronomy. Among which are the spots in the sun’s disk, by whose motion from west to east the sun is perceived to revolve upon his own axis in 25 days, 14 hours, 8 minutes. This revolution of the sun round his own axis is probably not the only motion which this luminary experiences. There is great reason to believe that he has another motion, either rectilinear, or round some indefinitely remote centre of attraction. In this last course, he carries along with him, through space, the entire system of planets, satellites, and comets; in the same manner in which each planet draws his satellites along with him in his motion round the sun. He communicates light and heat to at least twenty opaque bodies, which revolve round him, at different distances, in ellipses that differ but little from circles.

From the motion of the spots, which is sometimes straight and sometimes curved, we learn that the sun’s axis is not perpendicular to the plane of his ecliptic, but inclined to it, or the plane of the earth’s annual orbit, so as to form an angle of about 83 degrees. Christopher Scheiner, a most diligent observer of these spot’s in the sun’s disk, published a treatise concerning them in A.D. 1626. These spots are sometimes seen to increase to a very large size, and to continue for a considerable time. In the year 1779, there was a spot on the sun’s disk which was large enough to be seen with the naked eye: it was divided into two parts, and must have been 50,000 miles in diameter: this, and other phenomena of the same kind, may be accounted for from some natural change of the atmosphere. For if some of the fluids which enter into its composition be of a shining brilliancy, while others are merely transparent, then any temporary cause removing the lucid fluid, will permit us to see the body of the sun through the transparent ones. Dr. Herschell supposes that the spots in the sun are mountains on its surface, which, considering the great attraction exerted by this luminary upon bodies placed at its surface, and the slow revolution it has about its axis, he thinks may be more than 300 miles in height, and yet not be rendered unstable by the centrifugal force.

[There appears to be a discrepancy between this last statement—“Dr. Herschell supposes that the spots in the sun are mountains on his surface;”—and the statement made a few paragraphs preceding—“that what are called maculæ, or spots on the sun, Dr. Herschell thought to be real openings in his atmosphere, through which the opake body of the sun becomes visible.” These statements must have been made at different periods of his observations on the sun, which continued about fifteen years. The last statement was, doubtless, Dr. Herschell’s mature opinion.

As this seems to be a settled question among philosophers; and as it has induced the enlightened world to regard the sun as a habitable globe, it will not be out of place to enlarge a little on this point.

The spots on the sun’s surface has led to the conclusion above, and also to a determination of the motion of the sun around his own axis. They appear to have been observed, for the first time, in A.D. 1610, by Fabricius and Harriot; the first in Germany, the second in England. It is uncertain which noticed them first; but it is certain the discovery was original with both.

After the observations of these two fortunate persons were known, the attention of the scientific was directed to this phenomenon. Scheiner supposed the spots to be planets which revolved very near the sun. In process of unwearied observations, it was ascertained that these spots changed their positions. Sometimes two would blend together, and thus run into each other. Sometimes one large one would divide into two or three smaller ones. They were observed to dilate, and contract; and to have umbræ, or shades attending them.

From these phenomena Galileo and others supposed the solar spots were schoria floating on the burning liquid matter, of which they supposed the sun composed. M. de la Hire, and La Lande supposed them to be eminences which occasionally rose above the rolling tides of fire, as islands rise above the sea. All these theories were on the supposition that the sun was an igneous body, in a high state of combustion, by which means he dispenses heat and light to the surrounding planets.

Dr. Wilson, Professor of practical astronomy in the University of Glasgow, was the first to conjecture that these spots were depressions rather than elevations. This was about the year 1769. The Doctor rendered this conjecture very probable, by his close and lucid observations and illustrations.

These spots attracted the attention of the celebrated Dr. Herschell in 1779, who continued to observe them closely until 1794, and by means of his immensely large and powerful telescopes, he clearly established Dr. Wilson’s conjectures, that these spots are openings in the luminous surface of the sun, through which his opake body appears.

Dr. Herschell regards the real body of the sun to be an opake nucleus, fit for the habitation of intellectual creatures: that he has an atmosphere suited in density and height to his own magnitude: that in the higher regions of this atmosphere there are two sets of clouds surrounding the sun, which are permanently and essentially luminous, being phosphoric in their nature. The lower set of these clouds, which are next the sun, are less bright, and more dense than the upper set. They are designed to serve as a curtain to the sun’s body, to prevent a too great intensity of light at his real surface; the higher set of clouds, which are visible to us, being the principal source, or rather agent, of light.

It is plain from the foregoing theory, that we never see the real body of the sun, except when we see the spots on his surface: that what we commonly call the sun, are only those bright, luminous phosphorescent clouds, which permanently surround his body, and which give light outwards to the planets, and also inwards to his own inhabitants.

It will be obvious also to any one, that the inhabitants of the sun cannot see any heavenly body, as the stars, and planets; because they are inclosed by those clouds, which are impenetrable to vision. They may catch a glimpse of a passing star through these openings as we do of the sun’s body.

It is highly probable (see our paper on light, attached to our author’s chapter on the same,) that these luminous phosphoric clouds do not actually emit light, or heat; but only excite them at the surfaces of the different planets. That is: it is very probable there is a matter of light or a luminiferous ether, diffused through all existing matter, as caloric is, which is excited by these clouds, and thus becomes visible, which is light, as latent caloric is excited, and becomes sensible, by becoming free. Indeed it is very probable that the matter of heat and light is the same, and that heat and light are only different modifications of the action of the same substance, excited in a different, or higher degree.]