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phenomena; and, as one series of phenomena depends on another, so all existing phenomena are, in regard ta others, physically fit, compauble, and harmonious: and, as matter cannot originate its own motion, so, in cons sidering motion as the proximate cause of all phenomena, we arrive, through the ascending series, at the sublime FIRSTCA USE of all motion and all phenomena.

1. 509. Carbon is the base of almost all vegetable and animal substances. Charcoal is impure carbon; and diamond is pure carbon, except a small portion of oxygen with which it has been found to be combined. When combined with oxygen, it forms carbonie oxyde and carbonie acid gas.

-Carbon exists in large quantities in chalk, lime, stone, &c. From these it is procured in the form of gas, by adding sulphuric acid in a certain apparatus, and sold under the name of aerated or soda water, which is merely water impregnated with carbonic acid gas. Carbonic acid gas is the choke-damp o mines. Oils, fats, &c. are compounds of Carbon and hydrogen,

510. OXYGEN is an element or simple substance diffused generally through nature; and its different combinations are essential to animal life and combustion.

Combined with caloric, it becomes oxygen gas; 100 parts of atmospheric air contain 28 parts of axygen gas; and 100 parts of water consist of 85 oxygen and 15 nitrogen,

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Os. T—Oxygen gas is distinguished fivm all other gaseous matter by several important properties. Iudain

mable substances baru in it under the same circumstances as in common air, but with hifinitely greater vivichness. If a taper, the fame of which has been extinguished, the wick only remaining ignited, be plunged into a bottle filled with it, the flame will be luistantly rekindled, and will be very brilliant, and accompanied by a crackling noise. If a steel wire, or thin file, having a sharp point, armed with a bit of wood in combustion," be introduced

into a jar filled with the gas, the steel will take fire, and its combustion will continue to produce a most brilliant phenomenon.

2.-Oxygen gas is respirable; a small animal, eɩnfined in a jar filled with this gas, lives four or five tine 99 long as in an equal quantity of common air;--bencej it has been called vital air

511. During the burning of any combustible body, the oxygen leaves the atmospheric air, and combines with the cale or residuum, adding to its weight, and forming what is called un oxyde, or an acid.

Obs. 1-This process is called arygenation: and` if oxygen be combined with sulphur, phosphorus, carbon, or any other substance in various degrees, it will produce oxydes or acids of strength proportioned to the degree of oxygenation; which are distinguished by the terminations ous and ic; thus, in regard to sulphur and phosphorus, we vary,

.. Oxyde of sulphur; 2. Sulphurous acid;

3. Sulphuric acid.

1. Oxyde of phosphorus;
2. Phosphorous acid;

3. Phosphoric acid.

2.-Combined with metals in various degrees, oxygen produces oxydes of different colours; as grey oxyde of lead, red oxyde of lead, &c.

512. HYDROGEN is one of the most abundant principles in nature; and 15 parts of it combined with 85 of oxygen, form water.

It is only to be met with in the gaseous form; and, being 12 times lighter than atmospheric air, is employed to fill balloons.

It is also inflammable, and is the gas called the fire-damp, so often fatal to miners. It is the chief constituent of oils, fats, spirits, ether, coals, and bitumen.

Obs.-Hydrogen is always produced from water, aud WATER is formed by the union of oxygen with Hydro- * OEN. Its existence in water is manifested by water is

a state of vapour being made to pass over iron wire made red-hot, the oxygen of the water then combines with the iron, the water disappearing, and the hydrogen gas re

mains.

2. The process for filling balloons, is by mixing five parts of water with one of sulphuric acid; and, by pouring the mixture on iron filiigs, the light gas, by the decomposition of the water, will rise into the balloon; and the balloon, being 12 times lighter than the atmospheric air, will rise through it.

3.-Carburetted Hydrogen gas is now very extensively used in lighting the streets of London and other towns. It is distilled from coals, and purified by passing through lime-water. It is then conveyed into a reservoir, called a Gazometer, and from thence through pipes, to light streets, houses, churches, theatres, and shops.

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513. NITROGEN, or AZOTE, is a substance generally diffused through nature, and particularly found in animal bodies.

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Nitrogen is not to be found in a solid or liquid state; but, when combined with caloric, it forms azotic gas, in which no animal can breathe, og any combustible burn.

Seventy-eight parts combined with 22 parts oxygen, form 100 parts of atmospheric air. In a higher degree of oxygenation, as 30 to 70, it pro duces nitrous gas; and, still higher, nitric acul.

Obs. 1.-As oxygen is absorbed during burning of breathing, and as soon as the 22 parts, or nearly, of oxygeur are absorbed, the remainder is nitrogen, and becomes mephitic, or deadly, being incapable of sustaining life or flame.

2. The re-production of oxygen appears in the process of vegetation; healthy plants exposed in the sunshine to air, containing small quantities of carbonic acid gas, destroy that elastic fluid, and evolve oxygen gas; so that the two classes of organized beings are thus dependent.

3.It has lately been found, that azote generates urie acid, and gravel and stones in the kidneys, and hence animal food has properly been forbidden to persons subject to those afflicting disorders.

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514. CHLORINE, or Oxymuriatic Acid Gas, is an elementary substance, of a yellowish green colour; and it is this circumstance which suggested its name. Its odour is extremely disagreeable. It is not capable of being respired, and even when mixed in very small quantities with common air, renders the air extremely pernicious to the lungs. When an inflamed taper is introduced into a phial filled with it, the light continues, but of a dull red colour.

Obs.-Chlorine has never been found pure in nature; but exists in many compounds; particularly in common salt, and it may even be produced from that substance.

515. SULPHUR is an inflammable substance found in the neighbourhood of volcanoes, com

bined with earths and metals, from which it is separated by sublimation in a furnace,

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Obs. When combined with oxygen, it forms a subphuric and sulphurous acid. This is usually done by burning the sulphur in leaden chambers, the floors of which are covered with water, with a quantity of nitre (that is, one part to nine parts of sulphur) which a fords oxygen for the formation of the acid which is cons densed by the water. The water is then drawn off, eva porated by boiling, and afterwards distilled in retorts: the result is sulphuric acid, or oil of vitriol. Sulphur combines with hydrogen, the alkalies, the earths, and metals.. These combinations are called sulphurets.

620. Phosphorus is a simple substance, found in a state of combination with the bones of animals, from which it is extracted.

Its tendency to unite with oxygen is so great, that it always burns in the open air; and bursts into flame, at a degree of heat a little above that of the human body.

Its combinations with earths and metals are called phosphurets.

Obs. Many amusing experiments may be performed with it; but great care should be taken, and a basin of water kept at hand, for it will kindle Into an unextinguishable flame by slight friction.

521. Chemists, by separating earths from foreign matters, and from each other, have discovered nine primitive Earths, which are not soluble in water or by heat: they are,

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Lime,

Magnesia,

ObsThese earths combine with acids, alkalies, oxygen, sulphur, phosphorus, the metals, and with each other, in various proportions; and four of them merit special notice.

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