A Catechism of Familiar Things; Their History, and the Events Which Led to Their Discovery. With a Short Explanation of Some of the Principal Natural Phenomena. For the Use of Schools and Families. Enlarged and Revised Edition.

CHAPTER XXI.

Chapter 213,981 wordsPublic domain

ELECTRICITY, ELECTRIC CURRENTS, ELECTRIC BATTERY, ELECTROTYPING, STEREOTYPING, TELEGRAPH, OCEAN CABLE, LIGHTNING ROD, THE GULF STREAM, THE MT. CENIS TUNNEL, THE SUEZ CANAL, SUSPENSION BRIDGES, EMINENT AMERICANS.

What is the nature of Electricity?

A form of energy into which all other forms can readily be converted.

What is an Electric current?

Electricity manifests itself in a variety of ways, but all may be arranged under two heads, _viz._, 1, as a charge; 2, as a current. By means of friction, many bodies become electrified--that is, have acquired an electrical charge. If this charge is in great quantity we call it high tension. When a body containing an electrical charge is brought in contact with other bodies through which electricity is capable of passing, there ensues a current of electricity. Such bodies are called conductors.

What are the sources of currents?

There are currents produced by chemical action called voltaic currents; by the action of heat, or thermo-electric currents; by the motion of magnets, or magneto-electric currents.

What is positive and what negative electricity?

No difference in electricity in itself. When a body has more than its natural amount of electricity, it is said to be charged positively; when it has less than its natural amount it is negatively charged.

What is a Cell; what a Battery?

If a piece of zinc and copper joined by a wire be dipped in a liquid--generally weak sulphuric acid--which will act chemically on the metals, a current is produced. Such an arrangement is called a couple, or cell. If many cells are connected, then it is called a battery.

What is Thermo-electricity?

If two bars of any unlike metal--for example, antimony and bismuth--be soldered together at one end, and the other ends be connected by a wire and then the soldered end heated, a current will flow.

What effects are produced by currents?

They produce heat, light, decomposition and combination in liquid chemical compounds; they melt all metals, excite magnetism, and in the animal body excite movements of the muscles.

Can you specify these effects?

A strong battery produces heat in such a degree that all metals can be melted. Light is produced in flashes, or if the end of the leading wires are connected with two pencils of hard carbon, and brought very near together, then a brilliant light, or arc, called the voltaic arc, is produced. This is the dazzling bright light which we call electric light. The chemical effect of a current in decomposing compound substances is called electrolysis. In this way water can be decomposed into its compounds, hydrogen and oxygen; copper sulphate into sulphur and metallic copper, etc. In this way we can deposit strong adherent films of metal on the surface of any conductor; for if the article to be coated be attached to the negative electrode of a battery, and dipped into a solution of the metal with which we desire to coat the article, say copper or silver, and the positive electrode be attached to a plate of copper and also dipped into a liquid, when the current passes, the metal will be decomposed and deposited in a uniform layer over the article at the negative electrode. This process is called _electro-plating_.

What is Electrotyping?

It is the process of copying medals, type, wood-cuts, engraved copper and steel plates, etc., by means of electrical deposition. It is chiefly used for making, from the ordinary movable types, plates of fixed metallic types, for printing books.

Describe the process.

The article to be copied is first covered with black-lead, and then a mould is made of it in wax or gutta-percha. This mould is placed in a solution of sulphate of copper, and attached to the negative pole of the battery, while a plate of copper is hung from the positive pole. The electric current decomposes the copper, which is deposited in a thin film upon the mould. This film is removed and stiffened by being backed with metal.

What is the difference between Electrotyping and Stereotyping?

In stereotyping, a plaster of Paris mould is taken from the types, and upon this mould melted type-metal is poured, which, when hardened, makes a solid plate.

Is there any other method of stereotyping?

Yes; that known as the paper process. A uniform sheet of soft matter is formed by pasting together sheets of thin, tough tissue paper. The types are oiled, and the soft, moist sheet is placed on them and beaten down with a stiff brush until it receives an impression of the type-form. Both are then run through a press, and on being taken out the paper is found to form a perfect mould. Into this mould the type-metal is poured and the plate formed.

Can you tell me some magnetic effects of the current?

All conductors become magnetic during the passage of a current through them, and thereby acquire all the properties of a magnet. There are bodies which are natural magnets, and they are called permanent magnets. Those which become magnets only during the passage of a current are called electro-magnets.

Do you know any application of those magnets?

They are employed in a great variety of electrical apparatus, principally in telegraphy.

When was the first telegraph established?

It was made in 1836, being invented by Prof. Steinheil, of Munich, and adopted by the government of Bavaria. It was 12 miles long, and the signals were made by small bells.

Who was the inventor of the telegraph in this country?

Samuel F.B. Morse, who was born at Charlestown, Mass., April 27, 1791. He began life as a painter, but did not give his whole attention to art--chemistry and experiments in electricity and galvanism claiming much of his time. He first conceived the idea of the telegraph in 1832, and exhibited his invention to Congress in 1837. He struggled on with scanty means, and was about to give up in despair when Congress appropriated $30,000 for an experimental line, which was opened on May 12, 1844, between Washington and Baltimore. Prof. Morse died in 1872, but not before he had reaped honors and fortune from his invention.

How rapidly does the electric current travel through the wires?

From experiments made it appears to be about 15,400 miles in a second.

Can more than one message be sent at the same time on the same wire?

Yes; it is possible now to send several messages at the same time.

What is a Cable?

It is a telegraph wire under water. Prof. Morse, in 1842, laid a wire insulated by a covering of hemp coated with pitch-tar and India-rubber between Governor's Island and the Battery, New York. Several attempts were made in other countries.

What was the greatest telegraphic undertaking?

That of connecting Europe with America by a submarine cable spanning the ocean, which was commenced in 1857 and completed August 5, 1858.

To whom do we owe this grand undertaking?

This honor is entirely due to Mr. Cyrus W. Field. Mr. Field was born at Stockbridge, Mass., on November 30th, 1819. In 1853 he became interested in ocean telegraphy, and after many reverses succeeded in laying the first cable in August, 1858. The message sent by Queen Victoria to the President of the United States, consisting of 99 words, occupied 67 minutes in transmitting. In September of the same year this cable ceased to work, but the energy of Field restored confidence, and another cable was made and laid down in July, 1865, but after 1200 miles were deposited it was lost. In 1866 another was made and successfully laid in July. In August the lost cable was found and spliced, and carried to the western shore.

What is a Dynamo-electric machine?

A machine by which very powerful currents can be obtained directly from mechanical power. In these, by means of a steam-engine or other power, a number of coils of wire called the armature are set into rapid revolution between the poles of powerful electro-magnets. All currents are caused to flow from the armature in one direction by means of a contrivance called the commutator. Very successful machines of this sort are the Gramme machine, the Siemens, and, principally, the so-called Brush machine. By these the electric light is now generally produced.

What is a Lightning Rod?

It is a rod of iron placed against a building to protect it from lightning. Three or four feet of one end is in the moist ground or in water, while several feet of the other end extend above the highest part of the building. The upper end of the rod is pointed with copper or some other metal which will not easily corrode.

By whom was it invented?

By Benjamin Franklin, and first announced by him in his "Poor Richard's Almanac" for 1753. Franklin was born at Boston, Mass., in 1706. By his talents, prudence, and honesty he rose from humble beginnings to be one of the foremost men of his time. He was one of the committee of five chosen by Congress to prepare the "Declaration of Independence" which he with other patriots afterwards signed. Towards the close of the year 1776 he was sent as ambassador to the French Court, and remained in Europe some time. He returned home in 1785, and died at Philadelphia on the 17th of April, 1790.

What is the Gulf Stream?

It is a warm current in the Atlantic Ocean.

What is its origin?

It may be considered as beginning on the west coast of Africa, within the region of the trade winds. These cause a westward flow, known as the equatorial current. On reaching the coast of Brazil, the greater portion of this current bends northward, carrying with it the waters of the Amazon and Orinoco, and passes through the Caribbean Sea into the Gulf of Mexico. Here it is further heated, and rushes out through the only outlet, the Straits of Florida.

Describe its course.

Deep and narrow, it runs by Florida with a velocity varying from two to five miles an hour, and pressed by the cold current between it and the shore, flows parallel to the coast as far as Cape Hatteras. Meeting shoals near this point, the banks of sand extending as far as Newfoundland, it there turns abruptly to the east, and with diminished speed and increased width, rolls onward towards the coast of Europe. Before long it divides into two great branches--the northern and southern. The former extends as far as Spitzbergen; the latter, sweeping along by the Madeira and Canary Islands, returns to the equator, completing the circuit.

What influence has the Gulf Stream on the climate of Europe?

Various opinions have been expressed as to this. It has been estimated that the amount of heat arising from the stream on a winter's day, is sufficient to raise the atmosphere over the British Isles from the freezing point to a summer temperature.

How may the Gulf Stream be distinguished?

It can be distinctly traced in the ocean by its dark indigo color, its temperature, and the swiftness of its waters.

Which is the largest tunnel in the world?

The Mt. Cenis Tunnel, or the tunnel of Col de Frejus, by both of which names it is known. It is the longest subterranean route for commerce and travel yet constructed, being 7-1/4 miles in length. It is on the crest of the Cottian Alps, about 16 miles south-west of the summit of Mt. Cenis Pass. It was begun in 1857, and finished in 1871.

_Col_, a defile.

What other great engineering work can you mention?

The Suez Canal, a ship canal running across the Isthmus of Suez, and connecting the Mediterranean with the Red Sea. The canal is 100 miles in length, and through it an uninterrupted communication is established whereby large sailing vessels and steamers may pass from sea to sea, and thus avoid the long and dangerous voyage around the Cape of Good Hope.

To whom is the world indebted for this canal?

This great work owes its inception and completion to the enterprise and indomitable energy of Ferdinand de Lesseps, who was born at Versailles, France, on the 19th November, 1805. In January, 1856, he obtained a charter from the Egyptian Government for a company to construct the canal, and began work in 1859. Though beset by many difficulties, the persistent energy of De Lesseps fought its way to success, and in 1869 he had the satisfaction of seeing the waters of the Mediterranean and the Red Sea mingle in the Bitter Lakes. He has since been engaged in many engineering projects, the latest being a canal across the Isthmus of Panama to connect the Atlantic and Pacific oceans.

_Inception_, beginning.

_Indomitable_, not to be subdued.

_Persistent_, inclined to hold firm.

What is a Suspension Bridge?

A bridge supported by wires, ropes, or chains, which usually pass over high piers or columns at each end, and are secured in the ground below.

Name some of the largest bridges of this kind.

That at Niagara, those over the Allegheny at Pittsburg and the Ohio at Cincinnati, and the great East River bridge, which connects New York and Brooklyn.

Who planned these bridges?

John A. Roebling, who was born at Mulhausen, Prussia, June 12, 1806. In 1831 he emigrated to this country, and to his genius we are indebted for the bridges above named. The reports, plans, and specifications of the East River bridge were completed, and the work begun, when Roebling was severely injured in the foot while directing his work. Lockjaw succeeding amputation, he died in Brooklyn, July 22, 1869.

To what great Civil Engineer has the West given birth?

James B. Eads. Born at Lawrenceburg, Indiana, May 28, 1820, he began life as a clerk on a Mississippi river steam-boat. In 1842 he entered a firm engaged in recovering sunken property, and with such success that he retired with a fortune in 1857. During the civil war he devised a plan for the defence of the Western waters, and constructed several iron gun-boats with many novel features of his own invention. He has since acquired reputation as projecting and constructing engineer of the Illinois and St. Louis bridge, and by building jetties at the South Pass of the Mississippi, by which the depth of the river is increased, and it is made more navigable. These jetties are projecting dikes of brush, fascines, and stone.

_Fascines_, bundles of rods or of small sticks of wood, bound at both ends and at intermediate points, used in filling ditches, etc.

Give the names of some distinguished American inventors.

Eli Whitney, the inventor of the Cotton Gin, born in Westborough, Mass., 1765; died 1825. Jethro Wood, the inventor of the modern cast-iron plow, born at White Creek, N.Y., 1774; died 1834. Cyrus H. McCormick, inventor of the mowing machine, born at Walnut Grove, Virginia, in 1809.

Who was the inventor of the Sewing Machine?

Elias Howe. He was born at Spencer, Mass., July 9, 1819. When a boy he worked in a cotton mill at Lowell, but afterwards entered a machine shop in Boston. Here he conceived the idea of the sewing machine, and after long days of labor, part of which time he and his family lived on the kindness of a friend, he completed his invention. After many struggles, his talent, industry, and perseverance were rewarded, and long before his death, which occurred in October, 1867, he had acquired a large fortune.

INDEX.

Abyssinia, 142

Adhesion, 201

Affinity, Chemical, 197, 199

Air, 17 fixed, 112

Albert Durer, 130

Alchemy, 194

Alcohol, 137

Alexander, 161

Alexandria, 168

Allspice or Pimento, 51

Alluvial formations, 152

Almonds, 61

Alphabet, invention of, 43

Alum, 74

Alumina, 154

Amalgam, 20

Amber, 18

Ambergris, 66

Analysis and Combination, 195

Anemometer, 206

Angelo, Michael, 162

Anno Domini, 35

Apelles, 182

Apollo, 178

Arabic, gum, 94

Arabia, Felix and Deserta, 72

Archipelago, 32

Architecture, 156 orders of, 159, 160

Argil, 154

Armenia, 67

Arrow-root, 134

Arsenic, 126

Artesian Wells, 203

Arts, 190 liberal, 190 fine, 191 mechanical, 191

Art of writing, 191

Asbestus, 76, 78

Astronomy, science of, 187

Athenians, 23

Atmosphere, 17

Attraction, 201

Audiphone, 204

Aurora, the, 21

Aurora Borealis, 22

Australia, 31

Author, 54

Azores, islands of, 62

Azote gas, 113

Babel, tower of, 144

Babylon, 145

Bacon, Roger, 99

Baize, 32

Barbarians, 170, 183

Barilla or Soda, 105

Bark, 35 Peruvian, 36

Barley, 24 sugar, 49

Barometer, 96 Aneroid, 203

Barrel organ, 179

Bathometer, 206

Beaver, 70, 71, 74

Bell, A.G., 204

Black lead, 122

Blowpipe, 208

Bodies, natural, 197

Bombazine, 40

Books first printed, 59

Books, of what made, 37, 57

Bottles, 54

Box, musical, 179

Brandy, 137

Brass, 84

Bread-fruit, 86

Bricks, 144

Butter, vegetable, 87 tree, 87

Cable, 214

Cacao-nut tree, 27

Cadmus, 43

Calaminaris, Lapis, 84

Calcareous rocks, 150

Calico, 28

Caloric, 14, 114

Calomel, 97

Cambray, 41

Cambric, 41

Camera Obscura, 209

Camlet, 41

Camphor, 140

Candles, 106

Candy, Sugar, 49

Cannon, 100

Canoe, 36

Cantaleup, 67

Canvas, 33

Caoutchouc, 107

Capers, 61

Carbon, 112

Carbonic acid, 112

Carmine, 138

Carpets, 32

Carthage, 164

Cashmere shawls, 46

Cassia, 40

Castor or beaver, 70

Castor oil, 66

Cat, civet, 141 domestic, singular property of its fur, 19 gut, 179

Caviare, 135

Cayenne pepper, 53

Chaldea, 187

Chalk, 115

Charcoal, 81

Chemistry, 193-200

Cherry-tree, 35

Chinese or India ink, 76

China orange, 62

Chocolate, 27

Chronometer, 206

Chrysalis, 42

Cider, 136

Cinnamon, 39

Citrons, 62

Clay or argil, 154

Clocks, 98

Cloth, 29

Cloves, 38, 39

Coal, 81

Cochineal, 37, 38, 138

Cocoa-nut tree, 34

Coffee, 26

Cohesion, 201

Coin, 165

Combustion, 113

Compass, Mariners', 95

Commerce, 170

Constellations, 188

Consul, Roman, 147

Copernicus, 189

Copper, 83

Copperas, 75

Coral, 109-112

Cork, 37

Corn, 23

Cotton, 28 gins, 29

Cow-tree, 88

Crape, 40

Cretans, 23

Crimson, 138

Crusades, 172, 173

Crystallization, 14

Currants, 46

Cyrus, 146

Damask, 34

Dates, 68, 69

Decomposition, 196

Deluge, 191

Dew, 13, 14

Diamond, 127

Diaper, 33

Distillation, process of, 137

Drake, Sir Francis, 92

Dyeing, things used in, 138

Dynamite, 100

Dynamo-electric machine, 214

Eads, Jas. B, 218

Earths, 151 argillaceous, 152 calcareous, 150 silicious, 152

Earthenware, 55

Earthquakes, 155

Ear-trumpet, 204

Ebony, 132

Edison, Thos. A., 205

Egyptian Pyramids, 158

Egyptians, 23

Electrical machine, 19 properties in bodies, 19

Electricity, 18, 210

Electric Battery, 211 Current, 210

Electro-Magnet, 104 Magnetic Teleg'ph., 104, 213

Electron, 18

Electrotyping, 212

Elephant, 133

Emerald, 129

Engraving, 130

Ermine, 73

Etruscans, 182

Evergreen, 65

Fermentation, acetous, 138 vinous, 138

Ferro, 88

Field, Cyrus W., 214

Figs, 48

Fine arts, 191

Fitch, John, 103

Flannel, 34

Flax, 33

Flint, 153

Floating, 202

Florence, 64

Fossil or rock salt, 78

Franks, 170

Frankincense, 142

Franklin, Benj., 215

Fulton, Robert, 103

Fur, 73

Galileo, 101, 189

Galls, 75

Gamboge, 139

Gas, 114 hydrogen, 114 nitrogen or azote, 113 oxygen, 113

Gelatine, 135

Gems, 127

Genoa, 63, 172

Geologist, 151

Geology, 151

Geometry, 102

Gin, 137

Ginger, 50

Glass, 53 house, 54 windows, 54 looking, 55

Gloves, 73

Goat, Angora, 41

Gold, 118

Goths, 170

Granite, 148, 149

Gravitation, 201

Gravity, 202

Gray, Elisha, 205

Gulf Stream, 215

Gum, 93 arabic, 94

Gunpowder, 99, 100

Guns, 100

Hail, 16

Harp, 176

Hats, 70

Hemp, 33

Herculaneum, 154

Hermetic Seal, 96

Herschel, Sir William, 190

Hieroglyphics, 191

Holland, 33

Honey, 136

Hops, 137

Howe, Elias, 218

Hybla, 136

Hydrogen, 114

Hymettus, 136

Ice, 15

Idria, quicksilver mines of, 97

India rubber, 107 or Chinese ink, 76

Indigo, 138

Ink, 74 used by the ancients, 75

Inlaying, 132

Insect, coral, 109-111

Ionians, 60

Iron, 82

Isinglass, 132

Islands, Volcanic, 155

Ivory, 135

Jaca tree, 87

Japanese, 181

Jetties of the Mississippi, 218

Jupiter, 148

Kaleidoscope, 210

Kiln, 73

Lace, 41

Lapis calaminaris, 84

Laudanum, 91

Laws, How made, 148

Lead, 121 black, 122

Leather, 72

Legislative Powers, 147

Lemon, 62

Lenses, 95

Leo the Tenth, 184

Lesseps, Ferd. de, 217

Levant, 75

Libanus, Mount, 90

Licorice, 89

Light, 207 Drummond, 207 Electric, 208, 211 Lime, 207 Magnesium, 208

Lightning, 17 Rod, 215

Lime, a fruit, 63

Lime, an earth, 73, 112 quick, 150

Linen, 32

Liquids, 197, 198

Lithography, 131

Loadstone, 95

Logwood, 139

Lombards, 170

Lucca, 64

Lucullus, 35

Lungs, 89

Lyre, 178

McCormick, Cyrus H., 218

Mace, 51

Magic, 99

Mahogany, 107

Malt, 137

Maltese orange, 62

Mangoes, 85

Manioc plant, 134

Manna, 89, 90

Marble, 116 Parian, 117

Mariners' compass, 95

Marine salt, 78

Marl, 101

Mathematics, 101

Mead, 136

Mechanics, 102

Mediterranean, 171

Megaphone, 206

Melons, 67

Mercury, 97 the god, 178

Metals, primitive, 83

Metallurgy, 123

Microphone, 205

Microscope, 102

Milan, 40

Millet, 50

Mineral oil, 65 tar, 140

Mines, 84 coal, 81

Mint, 166

Mirrors, 54, 55

Mohair, 46

Mahomed, 72

Money, 163

Morphia, 91

Mortar, 148

Morse, S.F.B., 213

Mosque, 72

Mother-of-pearl, 132

Mt. Cenis Tunnel, 216

Muscles, 21

Music, vocal, 176

Musical instruments, 174 boxes, 179

Musk, 141

Myrrh, 141

Nantes, Edict of, 45

Natron, 105

Nature, kingdom of, 197

Navigation, 166-174

Nabuchodonosor, 146

Needles, 57

Nero, 185

New South Wales, 31

Newton, Sir Isaac, 189

Nicotine, 92

Nitre, 100

Nitrogen, 113

Northern Lights, 22

Nutmegs, 50

Oats, 24

Obelisk, 158

Oils, 65

Oil, olive, 64

Oil, castor, 66 mineral, 65

Olives, 63, 64

Olive branch, the emblem of Plenty, 64

Opium, 91

Orange, 61

Ore, 83

Organ, barrel, 179

Oxide, 83

Oxygen, 113

Painters, celebrated, 184

Painting, art of, 180

Palm, 68, 69

Palma Christi, 66, 67

Pantheon, 146

Paper, invention of, 57 mill, 58 linen, 58

Papyrus, 58

Parchment, 59

Pearls, 131

Pearl oyster, 131 barley, 24

Pendulum, 98

Pepper, 52 cayenne, 53

Pericles, 159

Perry, 136

Petroleum, 65

Phenicia, 54

Philosopher's stone, 194, 195

Phonograph, 205

Phosphorus, 125

Photography, 209

Pins, 57

Pimento, 51

Pisa, 172

Pitch, 140

Platina, 123

Pliny, 54, 182

Plumbago, 122

Poetry, 185-187

Poets, celebrated, 186

Polypus, 108

Pompeii, 154

Porcelain, 56

Potash, 53

Potatoes, 24

Primitive Earths, 153

Printing, 59

Prism, 208

Protestant, 58

Ptolemies, 189

Pyramid, 158

Pythagoras, 188

Quicksilver, 97

Rabbins, 55

Rain, 16

Rainbow, 208

Raisins, 47

Raleigh, Sir Walter, 92

Raphael, 183, 184

Refugee, 58

Republic, 65

Resin, gum, 93

Rhubarb, 94

Rice, 48

Rock or fossil salt, 78 calcareous, 150 transition, 151

Roebling, John A., 217

Rubies, 128

Rum, 137

Rye, 24

Sable, 74

Sago, 49 palm, 50

Salt, 78, 79 marine, 78 rock, 78 spring, 79

Saltpetre, 100

Saracens, 168

Scarlet, 138

Schools of painting, 184

Sciences, Arts and, 190

Sculpture, 160

Seal, an animal, 74

Senate, 147

Sesostris, 177

Seville orange, 62

Shoes, 72

Sicilians, 23

Sidon, 167

Silex, 153

Silicious earths, 152

Silk, 41, 45 worm, 42-43

Silver, 119

Slate, 149

Snow, 16

Soap, 105

Soda, 105

Specific Weight, 202

Spectacles, 94

Spectrum, 208

Spermaceti, 106

Spinning-jenny, 30

Spirits of wine, 137

Sponge, 108

Starch, 133

Steam engine, 102 navigation, 103

Steel, 150

Stethoscope, 204

Stereoscope, 209

Stereotyping, 212

Still, 137

Stockings, 71

Strata, 151

Suez Canal, 216

Sugar, 48 candy, 49 barley, 49 maple, 49

Sulphur, 124

Sumatra, 66

Suspension Bridges, 217

Tallow, 106 tree, 106

Tamarinds, 67

Tan, 73

Tapioca, 134

Tar, 139

Tasimeter, 206

Tasmania, 31

Tea, 25

Telegraph, 104, 213

Telephone, 204

Telescope, 101

Thebes, 43

Thermometer, 97

Thermo-Electricity, 211

Thibet Goat, 46

Thunder, 17

Tides, 201

Tin, 120

Tobacco, 91

Toddy, 34

Tortoise, 178

Tower, leaning of Pisa, 172

Troy, 177

Turpentine, 143

Turquois, 129

Tuscans, 182

Twilight, 21

Tyre, 167

United States Government, 147

Vapor, 14

Vellum, 60

Velvet, 45

Venice, 171

Venus, 171

Vine, 136

Vinegar, 138

Vitriol, 75

Volcanic formations, 152

Volcano, 154

Vulcanite, 108

Watches, 98

Water, 14 melon, 67 decomposition of by vegetables, 15 tree, 88

Wax, 106

Weaving, 30-32

Whale, 66

Whitney, Eli, 218

Wieliczca, 80

Wind, 17

Windows, 54

Wine, 136

Woad, 139

Wood, Jethro, 218

Wood engraving, 130

Wool, 29-31

Writing, art of, 191

Yams, 85

Zinc, 84

Zoophytes, 108

THE END.