MANY words, not contained in this GLOSSARY, will be found defined, or described in the body of the Work, in their proper places. For these, see Index.

Acanthus, a plant, growing in Greece and Italy.

Acescent, becoming sour.

Acetous, having the character of vinegar.

Acicular, shaped like needles.

Acid, a substance, or fluid, which turns vegetable blues to a red, and forms saline compounds with alkalies. Most of the acids contain oxygen.

Acropolis, the summit of a city, a citadel.

Affinity, the attraction between the particles of bodies, which causes them to enter into chemical combination.

Albumen, a substance found in living bodies, which coagulates by heat. White of egg is an example.

Alburnum, the soft or sap wood of trees, outside of the heart.

Alcohol, an inflammable liquid, which is the basis of ardent spirits.

Alhambra, a celebrated structure, built by the Moors at Granada, in Spain.

Alkali, a substance in chemistry, which turns vegetable blues to a green, and combines with acids, forming salts.

Alumine, an earth, which exists in clay, alum, &c.

Ammonia, volatile alkali.

Angle of incidence, the angle at which a ray falls on a reflecting surface.

Apollo de Belvidere, a celebrated antique statue, now in the Vatican at Rome.

A priori, from previous causes.

Aqueous, made with water.

Arc, part of a circle, or other curve.

Argillaceous, containing clay, or resembling it.

Argillaceous schist, common slate.

Atoms, or atomic weights, the original quantities, in which the different objects of chemistry combine with each other, considered in reference to another body.

Atrium, the principal hall in a Roman house. See page 62.

Augustan age, the time of the Roman Emperor Augustus.

Autograph, the original handwriting of a person.

Basalt, a rock, which is often found in regular blocks, forming columns, as in the Giant's Causeway, in Ireland.

Basilica, an ancient hall of justice.

Beau ideal, ideal beauty. Beauty surpassing what exists in Nature.

Bichloride, a double chloride. A compound, having two proportionals of chlorine.

Biliary concretions, lumps, which collect in the gall bladder, &c., of animals.

Bitartrate, any salt which has two proportionals of tartaric acid.

Borax, a salt, composed of boracic acid and soda.

Breccia, a kind of marble, composed of angular fragments, imbedded in a cement of a different color.

Cæcum, a part of the intestine.

Cæteris paribus, other things being equal.

Calcareous, consisting, chiefly, of Time.

Calcined, reduced, or altered, by heat, but not melted.

Camera lucida,) optical instruments, by which the images of things

Camera obscura, $ are thrown upon a paper, or other plane surface.

Cameræ vitreæ, glass chambers.

Campus Martins, the Field of Mars, or training-field of the Romans.

Caoutchouc, India rubber. See page 112.

Capillary attraction, the force by which fluids are drawn into minute cavities, or tubes; as oil in the wick of a lamp.

Carbonaceous, containing carbon or coal.

Carbon, a simple inflammable body, forming the principal part of wood and coal, and the whole of the diamond.

Carbonate, a compound or a salt, containing carbonic acid.

Carbonic acid, a compound gas, consisting of carbon and oxygen. It has lately been obtained in a solid form.

Carbonization, conversion into coal.

Carburetted hydrogen, a gas, composed of carbon and hydrogen; as coal gas.

Catacombs, tombs of large size, capable of containing many bodies.

Cellular, composed of little cells, or cavities.

Centaur, a fabulous animal, half man and half horse.

Centrifugal, tending away from the centre.

Chemical rays, rays of light, which occasion chemical changes in certain bodies.

Chloride, a compound of chlorine and some other substance.

Chlorine, a simple substance, formerly called oxymuriatic acid. In its pure state, it is a gas, and, like oxygen, supports the combustion of some inflammable substances.

Choragic, the name given to certain Grecian games, and to monuments erected in honor of those who conquered or excelled, in these games.

Chromate, a combination of chromic acid.

Chronometer, a watch, or time-keeper, of great accuracy, used in determining longitude.

Clepsydra, a water-clock.

Cloacæ, large drains, constructed under ground by the Romans.

Coliseum, or Colosseum, a large ancient amphitheatre, erected by the Emperor Vespasian, now standing at Rome.

Colossal, larger than life. Thus, a statue eight or ten feet high, is Colossal.

Comminuted, broken into fine fragments.

Concavo-convex, concave on one side, and convex on the other.

Conchoidal, rounded, like a shell.

Concrete juice, a juice which has become solid by drying.

Conic sections, the curves produced by cutting across a cone, in different directions.

Copal, a resin, used for varnishes.

Copperas, sulphate of iron.

Corrosive sublimate, a poisonous substance, called, in chemistry, bichloride of mercury.

Corundum, a very hard, crystallized stone, found in India and China.

Crystallization, the process of forming crystals.

Crystals. This name is given to the geometrical forms assumed by many bodies, especially salts and minerals.

Cuticle, the outer skin of a plant or animal.

Cyclopean walls, walls found in certain parts of Greece, which, from the great size of their stones, were fabled to have been constructed by ancient Cyclops, or giants.

Decoction, water in which part of a substance has been dissolved, by boiling.

Decompose, to separate the chemical constituents of a compound body.

Desideratum, a thing wanted, but not yet discovered.

Deoxidize, to deprive a substance of its oxygen.

Dextrine, a gummy matter, derived from starch. Its effects in the polarization of light will be found in the appropriate works.

Disc, a circular surface, which appears plane, or is so.

Druids, ancient priests of Britain.

Ductile, capable of being extended by drawing out, as in wire-making.

Eccentric, or excentric wheel, a wheel, the axle of which is not in the centre.

Empyreumatic, having a quality as if burnt.

Equilibrium, a state of rest, produced by the equal balancing of weight, pressure, or other forces.

Ether, a light, volatile liquid, prepared from alcohol and some acid.

Exfodiations, diggings, or excavations in the earth.

Extract, the juices of a plant, made solid, or partly so, by drying.

Facade, the front, or face, of a building.

Fac simile, an exact imitation, in writing, &c.

Fahrenheit, the inventor of the thermometer which is most used in this country.

Fecula, a vegetable principle, which forms the basis of flour and starch.

Feldspar, a hard kind of stone, found in granite. See page 84.

Ferrocyanite, a compound of the ferrocyanic acid with some base.

Filter., to strain through paper.

Fluate of lime, or Fluor spar, lime combined with fluoric acid. At Derbyshire, in England, it is found in crystalline masses, beautifully variegated with purple.

Forum, a public square at Rome, in which meetings of the people were held.

Fossils, substances found under ground.

Friable, easily reduced to powder.

Frustum, the lower part of a cone or pyramid, &c, cut off by a plane.

Fugacious, fading, or vanishing.

Fugitive color, fading, transitory.

Gas, a name applied to the different species of air, as oxygen gas, coal gas, &c

Gasometer, a vessel inverted in water, or other fluid, for the purpose of containing gases.

Galvanic, Galvanism, the kind of electricity which is developed by the combination of metals.

Gauls, the ancient inhabitants of Gaul, or France.

Ghizeh, a place on the banks of the Nile, near Cairo, celebrated for its pyramids.

Glaze, a transparent coating, or covering.

Gypsum, plaster of Paris, a kind of earth, consisting of sulphate of lime.

Hexagonal, six-sided.

Hieroglyphics, ancient letters, or characters, used, chiefly, by the Egyptians. Some of them were in the form of animals, instruments, &c.

Hydrate, a solid compound with water.

Hydrate of lime, a compound of lime with water.

Hydraulics, the science which treats of the motion of fluids.

Hydrochloric acid, see Muriatic Acid.

Hydrogen, a very light, inflammable gas, of which water is, in part, composed. It is used to inflate balloons.

Hydrostatics, the science which treats of the pressure of fluids.

Hydrosulphuret, a compound of hydrogen and sulphur with another body.

Ignited, heated red hot, or white hot.

Impluvium, part of a Roman house. See 62.

Incidence. See Angle of incidence.

Infusion, a solution of a vegetable substance, made without boiling.

Inspissated, thickened, as when the juice of a plant is partly dried.

Iodine, a simple substance of a grayish, black color, and metallic lustre, having a violet-colored vapor. It is obtained from marine plants.

Isinglass. This name is applied to a mineral substance, (see Mica, 86,) and also, to a kind of glue, or gelatin, procured from the swimming-bladders of certain fishes.

Labyrinth, an intricate building or passage, from which it was difficult to find the way out.

Lackers, or lacquers, varnishes for metals.

Lachrymatories, small urns, found in the tombs of the Greeks and Romans; so named, from their being supposed to contain the tears of the relatives of the deceased.

Lapidary, a workman in precious stones.

Lapis Albanus, a stone from Alba.

Lava, the melted substances ejected from volcanos.

Lentil, a kind of seed.

Levigated, rubbed into fine powder on a stone.

Ley, water which has percolated through ashes, earth, or other substances, dissolving and containing a part of their contents.

Lias, a fine-grained limestone used in lithography.

Lichen, a kind of moss, common on rocks, barks of trees, &c, of which there are many kinds.

Lime water, water in which lime is dissolved.

Litharge, an oxide of lead partly vitrified, or converted into glass.

Litre, a French measure, somewhat exceeding a quart.

Lozenge, a four-sided figure, like a rhomb, or a diamond on cards.

Louvre, a large building in Paris, containing pictures, and other works of art.

Magnesia, a kind of earth, light and white, with alkaline properties.

Maison Carrèe, "square house."

Malleable, capable of being spread out by hammering.

Manipulations, operations by hand.

Metre, a French measure, somewhat exceeding a yard.

Mica, isinglass. See 84 and 86.

Microscope, an optical instrument, which increases the apparent magnitude of objects.

Microscopic, too small to be seen, without a microscope.

Minerva, the ancient goddess of wisdom.

Minotaur, a fabulous monster, said to be half man and half bull.

Monolith, Monolithic, made of one stone. Thus, a monolithic column or statue consists of a single piece.

Mordant, a substance used in dyeing, to fix colors upon cloth.

Mummies, bodies of the dead, preserved by embalming and drying.

Muriatic acid, an acid, composed of chlorine and hydrogen, called, also, hydrochloric acid, and spirit of salt.

Naphtha, a kind of mineral tar.

Native, as found in Nature.

Nitre, or saltpetre, a salt, used in making gunpowder, &c. Nitrate of potass.

Nitric acid, an acid composed of oxygen and nitrogen.

Nitrogen, or azote, a simple substance, which exists, in the form of gas, in the atmosphere. It does not support respiration nor flame.

Nucleus, (plural Nuclei,) a centre. A kernel of a fruit.

Octagonal, eight-sided.

Oxidable, capable of being oxidized.

Oxidation, combination with oxygen; as in the rusting and tarnishing of metals.

Oxide, a compound (which is not acid) of a substance with oxygen:--Example, oxide of iron.

Oxygen, a simple and very important substance, which exists in the atmosphere, and supports the breathing of animals and the burning of combustibles.

Oxymuriatic acid. See Chlorine.

Pagoda, a Chinese tower.

Papyrus, a reed, of which the ancients made paper.

Parabolic, having the curved form of a parabola.

Parthenon, the temple of Minerva, at Athens.

Percolate, to trickle, or strain, through a porous body, as water passes through sand or ashes.

Peritoneum, the fine membrane which covers the intestines of animals.

Persepolis, an ancient city in Persia.

Pharos, a high tower. A lighthouse.

Photography. This word, by its etymology, means writing or engraving, by light.

Photometry, the measurement of light.

Physics, natural philosophy.

Piazza del Popolo, a square in modern Rome.

Pigments, coloring substances, used in painting.

Porcelain, fine earthen, or Chinaware.

Potass, an alkali, composed of potassium and oxygen.

Potassium, a light and very inflammable metal, discovered in potass, by Sir H. Davy.

Propylon, or Propylaeon, (plural Propylaea,) a large portico.

Proscenium, part of a theatre. See page 277.

Proto-sulphate, a compound of one proportional of sulphuric acid with a base.

Pyrites a metal, combined with sulphur, often in a crystalline form.

Pyroligneous acid, an acid, obtained from the smoke of wood.

Pyrometer, an instrument for measuring high degrees of heat, as in furnaces, &c.

Pumice stone, a very light, porous, gritty stone, of volcanic origin, used in polishing and grinding.

Puzzolana, see page 92.

Quartz, rock crystal. See page 84.

Quicklime, burnt limestone.

Reaumur, the inventor of a thermometer formerly used in France.

Refractory, difficult to fuse, or melt, in a furnace.

Relief or Relievo a mode of carving raised figures on a surface, like the head on a coin.

Repeating-watch, a watch which strikes the hour when a spring is pressed.

Residuum, the part which remains.

Resins, a kind of vegetable products, which are inflammable, and dissolve in spirit, but not in water.

Resinous, of the nature of resin, or rosin.

Retina, the part situated in the back of the eye, which is sensible to light.

Rhus copallinum, a species of sumach.

Sacristy, the part of a church in which the consecrated vessels, holy relics, &c, are kept.

Saracens, ancestors of the present Turks and Moors.

Saltpetre, see Nitre.

Sarcophagus, a stone coffin. Of these, there were many shapes.

Sardonyx, a kind of precious stone.

Savans, the French term for scientific men.

Scarabaei, beetles, insects held sacred by the Egyptians.

Scoria, slags. The refuse of furnaces, &c., after melting.

Segment, a part cut off by a plane.

Silex, an earth, of which glass is made. It exists in flints, sand, &c.

Silicious, containing silex, or flint.

Sistrum, an ancient musical instrument.

Size, glue, or gelatin, dissolved in water.

Solution, a liquid, having a substance dissolved in it.

Solvent, a fluid, capable of dissolving.

Souterrain, a place under ground.

Spatula, an instrument, with a broad blade, used for spreading.

Specific gravity, the weight of a body, as compared with that of water.

Spectrum, an image of seven different colors, produced by the rays of light passing through a prism.

Spheroid, a body, resembling a sphere in shape, but either longer, or more flat.

Sphinx, a fabulous animal, having the body of a lion and the head of a woman. The andro-sphinx had the head of a man.

Stadium, (plural stadia,) a Greek and Roman measure. A furlong. Also, a race-course.

Sublimation. In chemistry, a substance is said to be sublimed, when it passes, by heat, from a solid form to that of gas, without melting.

Subtend, to reach across, between two lines which make an angle.

Sulphur, or brimstone, a simple, inflammable substance, well known.

Sulphuret, a compound of sulphur with another body.

Sulphuretted hydrogen, a gas, composed of sulphur and hydrogen.

Sulphuric acid, an acid composed of oxygen and sulphur.

Suspended, floating, or mixed, but not dissolved.

Syphon, a crooked tube, in which water running down the longer half will cause water to run up the shorter half, by atmospheric pressure.

Tamarisk, a tree, growing in countries about the Mediterranean.

Tambours, or frusta, the round blocks of which columns are made up.

Tannin, a substance, found in the oak, and other trees and plants; used in tanning hides.

Tanno-gallate, a combination of tannin and gallic acid with another substance.

Tartar, a substance, deposited on the inside of wine casks, consisting chiefly of tartaric acid and potass.

Terra cotta, baked earth, or burnt clay.

Thermae, baths of the Romans, which were large and magnificent buildings.

Thermometer, an instrument, for measuring heat.

Trapezoid, an irregular figure of four sides, no two of which are parallel.

Unguent, ointment.

Vatican, a palace at Rome, the Winter residence of the Pope. It is celebrated for its vast collection of works of art. It contains upwards of four thousand rooms, many of which are filled with rare and costly paintings, statues, an immense library, &c.

Veneering, the art of covering wood with a thin layer of wood of a different kind.

Venus de Medicis, a celebrated antique statue of great beauty, now at Florence.

Verdigris, an acetate of copper, used as a paint.

Vestibulum., the threshold of a house. See page 62.

Villa, a country seat, or residence.

Vinous, having the character of wine.

Volatile oils, oils which evaporate by moderate heat.