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and the chymical action of acids and alkalies, and of the minutest particles of matter upon each other—ought to be viewed as so many modifications of the agency of Deity, and as manifestations of his wisdom, in carrying forward those plans which regard the interests of his universal kingdom; just as we consider the rise and fall of empires, the revolutions of nations, and the circulation of the Scriptures in heathen lands, as so many acts of his moral administration as the Governor of mankind. For let it be carefiilly remembered, that all these physical agencies have ultimately a moral and intellectual bearing; and are essentially connected with every other part of God's providential procedure. Though we may be apt to consider them as so many detached and insulated piece? of machinery, with which we have little concern, 'w may even disdain to notice their mode of operation; yet, in the allcomprehensive mind of Him who takes in, at one glance, the whole chain of causes and effects, they are as essentially connected with his ultimate purposes, and the eternal destiny of man, as are the revelations of his word. Were a single principle or motion which now animates the system of nature to cease—were the agencies of electricity, for example, or the principle of evaporation, to be destroyed—the physical constitution of our globe would instantly be deranged; nature would be thrown into confusion; and the sentient and intellectual beings that now inhahit the earth would cither be destroyed, or plunged into an abyss of misery. If, therefore, we admit that the moral agency of God is worthy of our contemplation, we ought to consider his physical operations also as no less worthy of our study and investigation; since they form the groundwork of all his other manifestations.

There is nothing, however, which so strikingly characterizes the bulk of mankind, and even the great mass of the Christian world, as that apathy and indifference with which they view the wonders of creation which surround them. They can look on all that is grand, and beautiful, and beneficent in nature, without feeling the least sentiment of admiration, or of gratitude to that Being who is incessantly operating within them and around them ; and they are disposed to consider the experiments of philosophers, by which the wonderful agency of God is unveiled, as only so many toys and amusements for the entertainment of children. They would prefer the paltry entertainments of a card-table, of a ball-room, or of a goesipping party, to the inspection of the nicest pieces of divine mechanism, and to the contemplation of the most august scene in nature. However lightly some religionists may be disposed to treat this subject, that spirit of indifference with which the visible works of God are treated must be considered as flowing from the same depraved principle which leads multitudes to reject the revelations of the Bible, and to trifle

with their everlasting interests. "Man,*' say Rollin, " lives in the midst of a world of wme* he is the sovereign, as a stranger, who look* with indifference upon all that passes in it, and as if it was not his concern. The universe, it all its parts, declares and points out its Author; but, for the most part, to the deaf and blind, who have neither ears to hear, nor eyes to see. One of the greatest services that philosophy can bo us, is to awaken us from this drowsiness, and rouse us from this lethargy, which is a dishonour to humanity, and in a manner reduces us below the beasts, whose stupidity is the consequence of their nature, and not the effect of neglect or in difference. It awakens our curiosity, it excites ourattention, and leads us as it were by the hand, through all the parts of nature, to induce us to study and search out the wonderful works of it." —Belle* Lettres, vol. 4.

Since, therefore, the science of natural philosophy is conversant about the works of the AW mtghty, and its investigations have a direct tendency to illustrate the perfections of his nature, to unveil the plan of his operations, to unfold the laws by which he governs the kingdom of universal nature, and to display the order, symmetry, and proportion, which reign throughout the whole—it would be needless to enter into any further process of reasoning, to show that the study of it is connected with the great objects of religion. Whatever studies tend to raise our minds to the Supreme Ruler of all worlds—to expand our views of his infinite knowledge and wisdom—to excite our gratitude and our admiration of the beneficent designs which appear in all his arrangements—to guard us against erroneous conceptions of his providential procedure— and to furnish us with important auxiliaries for extending the influence of his religion through the world; must always be interesting to every Christian who wishes to enlarge his intellectual views, and to make progress in the knowledge of God.

CHYMISTAY.

This science, which is intimately related te the preceding, has for its object to ascertain the ingredients, or first principles, of which all matter is composed—to examine the compounds formed by the comhination of these ingredients—to investigate those changes in natural bodies, which are not accompanied with scnsible motion, and the nature of the power which produces these comhinations and changes.

Within the limits of the last half century, the empire of chymistry has been wonderfully extended. From an obscure and humblo place among the objects of study, it has risen to a Inch and dignified station among those sciences whirb improve and adorn the human mind. No longer confined to the paltry and mercenary object of searching for the philosopher's stone, or of furnishing a little amusement, it now extends its sway over all the arts which minister to the comfort and improvement of social life, and over every species of animate and inanimate matter, within the range of human investigation. "The forms and appearances," (says Sir Humphrey Davy,) "of the beings aud substances of ihe external world, are almost infinitely various, and nicy are in a slate of continued alteration. Even the earth itself, throughout its whole surface, undergoes modifications. Acted on by moisture and air, it affjrds the food of plants; an immense number of vegetable productions arise from apparently the same materials; these become the substance of animals; one species of animal matter is converted into another; the most perfect and beautiful of the forms of organized life ultimately decay, and are resolved into inorganic a* gr eg rates; and the same elementary substances, differently arranged, are contained in the inert soil, or bloom and emit fragrance in the flower, or become in animals the active organs of mind and intelligence. In artificial operations, changes of the same order occur; substances having the characters of earth, are converted into metals; clays and sands are united, so as to become porcelain; earths and alkalies are comhined into glass; acrid and corrosive matters are formed from tasteless substances; Colours are fixed upon stuff-, or changed, or made to disappear; and the productions of the vegetable, mineral, and animal kingdoms are converted into new forms, and made subservient to the purposes of civilixed life. To trace, in detail, these diversified and complicated phenomena; to arrange them, and deduce general laws from their analogies, is the business of chymistry."— Elements of Chymical Philosophy.

Cbymists have arranged the general form* of mutter into the (bur following classes. The^ref class consists of Solids, which firm the principal parts of the globe, and which differ from each other in hardness, colour, opacity, transparency, density, and other properties. The second class consists of Fluids, such as water, oils, spirits, &c., whose parts possess freedom of motion, and require great mechanical force to make them occupy a smaller space. The third class comprehends Elastic Fluids, or Gases, which exist freely in the atmosphere; but may be confined by solids and fluids, and their properties examined. Their parts are highly moveable, compressible, and expansive; they are all transparent; they present two or three varieties of colour; and they differ greatly in density. The fourth class comprehends Ethereal Substance*, which are known to us only in their states of motion, when acting upon our organs of sense, and which are not susceptible of being confined. Such are the rays of light, and radiant heat, which are incessantly in mo ion, throughout the spxces that intervene between our globe and the sun and the •Cart. Chymists divide the substances in nature

also into simple and compound. Simple Subttanees are those which have never yel oeen decomposed, nor formed by art. Compound Substances are those which are formed by the union of two or more simple substances. The following are all the simple substances, with which we are at present acquainted: Calorie, Light, Oxygen, Nitrogen, Carbon, Hydrogen, Sulphur, Phosphorus, the Metal*, and some of the Earth*. All that I propose, under this article, is, simply to state some of the properties of two or three of these simple substances.

Calorie, or elementary fire, is the name now given by chymists to that element or property which, comhined with various bodies, produces the sensation of heat, while it is passing from one body to another. This substance appears to pervade the whole system of nature. There are six different sources, from whence caloric may be procured. It may be produced by combustion, in which process the oxygon gas of the atmosphere is decomposed, and caloric, one of its component parts, set at liberty—bv fnrtinn, or the rubhing of two substances against each other—by percussion, as the striking of steel against a piece of flint—by the mixture of two or more substance*; as when sulphuric acid is poured upon water or magnesia—by electricity and galvanism. The discharge of an electric or galvanic battery will produce a more intense degree of heat than any other means whatever. But the principal, and probably the original source of caloric, is the Sunf which furnishes the earth with a regular supply for the support and nourishment yC the animal and vegetable tribes. From this source it moves at the rate of 195,000 miles in a second of time; for it has been already stated, that the sun sends forth rays of heat, which are distinct from those which produce illumination, and which accompany them in their course through the ethereal regions.

Caloric is the cause of fluidity, in all substances which are capable of becoming fluid. A certain portion, or dose of it, reduces a solid body to the state of an incompressible fluid ; a larger portion brings it to the state of an aeriform or gaseous fluid. Thus, a certain portion of caloric reduces ice to a state of water ; a larger portion converts it into steam or vapour. There is reason to believe that the hardest rocks, the densest metals, and every solid substance on the face of the earth, might be converted into a fluid, and even into a gas, were they submitted to the action of a very high temperature. This substance is called setutbfe caloric, when it produces the sensation of heat; and latent caloric, when it forms an insensible part of the substance of bodies. All bodies are, in a greater or less degree, conductor* of caloric. Metals and liquids are good conductors of heat, but silk, cotton, wool, wood, &c. are bad conductors of it. For example, if we put a short poker into the fire at one end, it wilt soon become hot at the other ; but this will not happen with a piece of wood of the same length, and under the same circumstances. A person with a silken purse, containing metal coin, may stand so near the tire, as to make the metal almost too hot to touch, though the temperature of the purse will apparently be scarcely altered. If a hand be put upon a hot body, part of the caloric leaves the hot body and enters the hand, producing the sensation of heat. On the contrary, if a hand be put on a cold body, as a piece of iron, or another cold hand, part of the caloric contained in the hand leaves it to unite with the colder body, producing ihe sensation of cold. In short, caloric is diffused throughout all bodies, and enters into every operation in nature; and were it not for* the influence of this subtile fluid, there is reason to believe, that the whole matter of the wiiverse would be condensed into a solid mass.

Oxygen is a very pure, subtile, and elastic substance, generally diffused throughout nature; but is never found unless in combination with other substances. It is one of the most important agents in nature; there being scarcely a single process, whether natural or artificial, in which oxygen has not some important share. When combined with caloric, it is called oxygen gas, which forms one of the constituent parts of the atmosphere. In this state, it forms the principle of combustion; producing the most rapid deflagration of all combustible substances. If a lighted taper be let down into ajar of oxygen gas, it burns wiiii such splendour, that th«. eye can scarcely bear theglar e of light ; and at the same time produces a much greater heat than when burning in common air. If a steel wire, or a thin file, having a sharp point, armed with a bLl of wood in inflammation, be introduced into a jar filled with this gas, the steel will take fire, and its combustion will continue, producing a most brilliant phenomenon. It has been proved, by numerous experiments, that this gas is so essential to combustion, that no substance will burn in common air, which has been previously deprived of its oxygen. It is also essential to animal life; so that man, and all the inferior ranks of animated nature, may be said to depend upon this fluid for their existence. Its basis gives the acid character to all mineral and vegetable salts: and the calcination of metals is altogether effected by their union with oxygen. It constitutes the basis both of the atmosphere which surrounds the earth, and of the water which forms its rivers, seas, and oceans. It pervades the substance of all the vegetable tribes, and enables them to perform their functions; and, ia combination with the different metals, serves the most important purposes in the useful aria. In the operation of this elementary principle, we perceive a striking^1isplay of the ag'.nt-y of the Creator, and of the admirable

means which his wisdom has contrived for preserving, in due order, the system of nature. And, as this wonderful substance is so essentially necessary to animal and vegetable existence, every thing is so arranged as to produce a regular supply of it, notwithstanding its incessant changes, and the multifarious combinations into which it is continually entering.

One of the must extraordinary effects of oxygen appears, when it is combined in a certain proportion with nitrogen, so as to form the gaseous oxide of nitrogen, or what is commonly called nitrous oxide. This gas consists of 63 parts nitrogen, and 37 oxygen, by weight. When inhaled into the lungs, it produces an exlrarsdinary elevation of the animal spirits, a propensity to leaping and running, involuntary fits of laughter, a rapid flow of vivid ideas, and a thousand delightful emotions; without being accompanied with any subsequent feelings of debility. This circumstance shows what a variety of delightful or pernicious effects might flow from the slightest change in the constitution of the atmosphere, were the hand of ihe Almighty to interpose in altering the proportion of its constituent parts: for atmospheric air is composed of 79 parts of nitrogen, and 2I of oxygen, which is not a very different proportion from the above. Another gas called nitric oxide, composed of 56 parts oxygen, and 44 nitrogen, produces instant suffocation in all animals that attempt to breathe it. One of the most corrosive acids, the nitrous acid, or aquafortis, is composed of 75 parts oxygen and 15 parts nitrogen; so that we are every moment breathing a certain substance, which, in another combination, would produce the most dreadful pain, and cause our immediate destruction. What a striking proof does this afford of the infinite comprehension of the divine mind, in foreseeing all the consequences of the elements of nature, and in directing their numerous combinations in such a manner as to promote the happiness of animated beings \

Nitrogen, or azote, is a substance generally diffused throughout nature, and particularly in animated bodies. It is not to be found in a solid or liquid state, but, combined with caloric, it forms nitrogen gas, which is one of the ingredients of the atmosphere It is capable of supporting either flame or animal life. This is proved by introducing an animal, or a burning candle, into a vessel full of this gas: in which case, the animal is suddenly suffocated, and the candle instantly extinguished. It is this gas which is expelled from the lungs at every respiration, and, rising over our heads, soon enters into new combinations. Though it is destructive to animal life, it appears to be favourable to plants, which vegetate freely when surrounded with nitrogen.

Hydrogen is another elementary sulistance, abundant in nature, and, when united to caloric (xm* hydrogen gas. It in one of the constituent parts of wafer; for it has been completely demonstrated by experiment, that water is composed of 85 parts by weight of oxygen, and 15 of hydrogen, in every hundred parts of the fluid. This gn was formally known by the name of inflammable air. It is distinguished among miners by the name of jrre-damp; it abounds in coal-mines, and sometimes produces the most tremendous explosions. It Is incapable, by itself, of supporting combustion, and cannot be breathed without the most imminent danger. It is the chief constituent of oils, fats, spirits, ether, coals, and hitumen; and is supposed to be one of the agents which produce the igne« faiui and the northern UghtM. It is the lightest of all ponderable bodies; being from twelve to fifteen times lighter than common air. A hundred cuhic inches of it weigh ahout 2| grains. On account of its great levity it is used for filling air-balloons. In contact with atmospheric air, it burns with a pale blue colour. When mixed with oxygen gas, it may be exploded like gunpowder, with a violent report. Carbureted hydrogen gam, which Li carbon dissolved in hydrogen, is that beautiful gas, which is now employed in lighting our streets, shops, and manufactories.

Carton is another simple substance extensively diffused throughout nature. It is found pure and solid only in the diamond; but it may be procured in the state of charcoal, by burning a piece of wool closely covered with sand, in a crucible. Carbon enters into the composition of hitumen and pit coal, and of most animal and some mineral substances; and it forms nearly the whole of the solid basis of all vegetables, from the most delicate flower to the stately oak. It is also a component part of sugar, and of all kinds of wax, oils, gums, and resins. It comhines with iron in various proportions, and the results •re cast iron and steel. Black lead is a composition of nine parts of carbon to one of iron; and is, therefore, called a carburet of iron. Carbon is indestructible by age, and preserves its identity in all the comhinations into which it enters. Carbonic add gas is a comhination of carbon and oxygen. It u found in a state of comhination with lime, forming limestone, marble, and chalk; and mav be separated from them by heat, or by means of thamineral acids. This gas, which was formerly called fixed air, is found in mines, caves, the bottoms of wells, wine cellars, brewers' vats, and in the neighbourhood of lime-kilns. It is cnown to miners by the name of the choke-damp, and too frequently runs on deadly errands. It extinguishes flame and animal life. It is the heaviest of all the gases; being nearly twice the weifht of common air, and twenty times the weight of hvdrogen. tt may, therefore, be poured from one vessel to another; and if a •mall quantity of it be poured upon a lighted taper, it wrll be instantly extinguished. It is a

powerful antiseptic, or preserver from putrefaction. Meat which has been sealed up in it (says Mr. Parkes) has been known to have preserved its texture and appearance for more than twenty years. There is no substance of more importance in civilized life than the different forms of Carbon. "In nature," says Sir. H. Davy, M this element is constantly active in an import* ant series of operations. It is evolved in fermentation and combustion, in carbonic acid; it is separated from oxygen in the organs of plants, it is a principal element in animal structures; and is found in different forms in almost alt Hie products of organized beings."

Sulphur is a substance which has been known from the earliest ages. It was used by the ancients in medicine, and its fumes have, for more than 2000 years, been employed ifftbleaching wool. It is found comhined w^i'h many mineral substances, as arsenic, antimony, copper, and most of the metallic ores. It exists in many mineral waters, and in comhination with vegetable and animal matters, but is most abundant in vulcanic countries, particularly in the neighbourhood of Vesuvius, Etna, and Hccla in Iceland. It is a solid, opaque, combustible substance, of a pale yellow colour, very brittle, and almost without taste or smell. Its specific gravity is nearly twice that of water; it is a con-conductor of electricity, and, of course, becomes electric by friction. When heated to the temperature of 170o of Fahrenheit's thermometer, it rises up in the form of a fine powder, which is easily collected in a proper vessel, and is named the flowers of sulphur. It is insoluble in water, but may be dissolved iti oils, in spirit of wine, and in hydrogen gas. When sulphur is healed to the temperature of 302o in the open air, it takes Are spontaneously, and bums with a pale blue flame, and emits a great quantity of fumes of a strong suffocating odour. When heated to the temperature of 570o, it burns with a bright white flame, and emits a vast quantity of fumes. When these fumes are collected, they are found to consist entirely of sulphuric add; to that sulphur, by combustion, is converted into an acid. It is the base of several compound substances. It unites with oxygen, hydrogen, nitrogen, phosphorus, the alkalies, the metals, ami some of the earths. This substance is of great importance in medicine, as it is found to penetrate to the extremities of the most minute vessels, and to impregnate all the secretions. It is also used in the arts, particularly in bleaching and dying; it forms a very large proportion of gunpowder ; and one of its most common, but not least useful properties, is that of its combuMAiHty, by which, with the help of a tinder-box, light is almost instantaneously produced. As this substance has not yet been decomposed, it is considered by chyroists, in the mean time, as one of the simple substances.

Phosphorus is another simple combustible substance, but is never found in a pure state in nature. It is commonly united to oxygen in a state of phosphoric acid, which is found in different animal, vegetable, and mineral substances. It was first discovered by Brandt, a chymist of Hamburgh, in the year 1667, and afterwards by the Honourable Mr. Boyle, in 1679. It was formerly obtained by a disgusting process; but it is now extracted from the bones of animals, by burning them, and then reducing them to a fine powder, and afterwards pouring sulphuric acid upon them. This substance, when pure, resembles bees' wax, being of a clear, transparent, yellowish colour; it is insoluble in water; it may be cut with a knife, or twisted to pieces with the fingers; and it is about double the specific gravity ojfeater. Its most remarkable property is its very strong attraction for oxygen, from which circumstance, it bums spontaneously in the open air at the temperature of 43o; that is, it attracts the oxygen gas from the atmosphere, and heat and flame are produced. It gradually consumes when exposed to the common temperature of air, emits a whitish smoke, and is luminous in the dark; for this reason it is kept in phials of water; and as the heat of the hand is sufficient to inflame it, it should seldom be handled except under water. At the temperature of 99» it melts; it evaporates at 2l9o, and boils at 554». When heated to 148o it takes fire, and bums with a very bright flame, and gives out a very large quantity of white smoke, which ^is luminous in the dark; at the same time it emits an odour, which has some resemblance to that of garlic ; and this smoke, when collected, is proved to be an add. It burns with the greatest splendour in oxygen gas, and when taken internally, it is found to be poisonous. If any tight substance, capable of conducting heat, be placed upon the surface of boiling water, and a hit of phosphorus be laid upon it, the heat of the water will bj sufficient to set the phosphorus on fire, 1f we write a few words on paper with a hit of phosphorus fixed in a quill, when the writing is carried into a dark room it will appear beautifully luminous. If a piece of phosphorus, about the size of a pea, be dropped into a tumbler of hot water, and a stream of oxygen gas forced directly upon it, it will display the most brilliant combustion under water that can be imagined. All experiments with phosphorus, however, require to be performed with great caution. This substance is used in making phosphorus matehoo'tles, phosphoria oil, phosphoric tapers, and various phosphoric fireworks. Phosphorixed Aydrogsn gas is produced by hits of phosphorus remaining soms hours in hydrogen gas. It is supposed to be this gas which is often seen hovering on the surface of burial grounds and marshes, known in Scotland by the name of tpuntoe, and in England by that of wiU-o-the-wisp.

Some animals, as the glowworm and thcjtr* Jly, and fish in a putrescent state, exhihit phosphorescent qualities. M. Peron describes a singular instance of this kind in an animal which he calls the pyrosoma atlanticum, which he observed in his voyage from Europe to the Isle of France The darkness was intense when it was first discovered; and all at once there appeared at some distance, as it were, a vast sheet of phosphorus floating on the waves, which occupied a great space before the vessel. When the vessel had passed through this inflamed part of the sea, it was found that this prodigious light was occasioned by an immense number of small animals, which swam at different depths, and appeared to assume various forms. Those which were deepest looked like great red-hot cannon balls, while those on the surface resembled cylinders of redhot iron. Some of them were caught, and were found to vary in size from ihreeto seven inches. All the exterior surface of the animal was bristled with thick long tubercles, shining like so many diamonds; and these seemed to be the principal seat of its wonderful phosphorescence.

Such is a brief description of the principal elementary substances, which, in a thousand diversified forms, pervade the system of nature, and produce all that variety which we behold in the atmosphere, the waters, the earth, and the various processes of the arts. It is probable that some of these substances are compounds, though they have not yet been decomposed. Yea, it is possible, and not at all improbable, that there are but two, or at most three, elementary substances in nature, the various modifications of which produce all the beauties and sublimities in the universe. Perhaps caloric, oxygen, and hydro, gen, may ultimately be found to constitute all the elementary principles of nature. Without prosecuting this subject farther, I shall conclude this article with a few cursory reflections, tending to illustrate its connexion with religion.

The remarks which I have already thrown out in reference to natural philosophy will equally apply to the science of chymistry; and, therefore, do not require to be repeated. In addition to these, the following observations may be stated r—

1. This science displays, in a striking point of view, the wisdom and goodness of God, in produdng, by the most simpfe means, the most astonishing and benevolent effects. All the varied phenomena we perceive, throughout the whole system of sublunary nature, are produced by a comhination of six or seven simple substances. I formerly adverted to the inAnite variety which exists in the vegetable kingdom, (see pp. 37, 38.) About fifty-six thousand different species of plants have already been discovered by botanists. All these, from the humble shrub to the cedar of Lebanon, which a dorr* the surface of the globe, in every clime, witk

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