Chapter LX: Some Curious Modes of Transit

We have already noticed some novel means of locomotion in the water and in the air, and now a few of the means whereby locomotion is attained as a recreation or as an exhibition may be mentioned.

For instance, here is a very curious vehicle, and the explanation of it we give in the words of the anonymous inventor:—

“My vehicle will carry four people without counting the driver. It is strong, easy to draw, and can turn in a horse’s length. The driver completely controls the animal, and no dust is thrown up to inconvenience the sitters, for by the time it rises the car is well in advance of it. It is cheap; the harness is simple and safe. The horse is sheltered from heat and rain and flies. If he should fall, there is no more than ordinary danger to life and limb than if he fell in a carriage; and, last of all, no very showy animal is needed, so long as his wind is sound, and his legs and tail respectable. Travellers in this “trap” can sit in any position, back to back, or face to face, two and two. The weight is all near the collar, and the animal is under control most perfectly.

“The estimated cost is £40; the horse about £40, or less; harness (say), £7, which contrasts favourably with the expenses of an ordinary one horse vehicle.”

ENDLESS RAILS.

These adjuncts to locomotion can be adapted to any kind of vehicle, and are in pieces about two feet long, articulated, and resting upon a base to give the necessary stability. The endless rail entirely envelopes the wheels all along the train, and the right and left rails are quite independent of each other, and as the vehicles advance the rails are put down and raised again when the carriages have passed. In front there are two distributing wheels governed by the tractive power, so that as the engine, or the animal drawing the train turns aside, the rails are still laid down parallel as before, but the hind wheels will not permit of very sharp curves.

There are wheels also at the rear of the train, and as on curves one wheel will pass over more rail than another, and in the hinder wheels a differential arrangement is used, and when one goes back the other advances as much, and so the relative distance is kept up, for the rail does not alter in length at all. The wheels have double flanges to retain them on the line.

The system, considered from a mechanical point of view, gives striking results, and very little effort is required to put the train in motion. The resistance is very small, and much greater weights can, of course, be transported upon the endless rail than upon the ordinary road.

The experiment has been tried in the Tuilleries Gardens in Paris. Three carriages filled with children are drawn by two goats without any fatigue, and in the ordinary goat carriages at least twelve of the animals would be necessary—that is, four to each carriage. The economy of this mode of transport is therefore incontestable. The usual rate is about three-and-a-half to four miles an hour, so it is not adapted for travellers, but for merchandise.

The system might be applied to numerous vehicles on all kinds of roads for horses and oxen, in mines and factories, and in colonial plantations. M. Ader, the inventor, intended the system to be applied in the Landes, where the rails would lie close upon the sandy soil, and the expense of “metalling” roads would be entirely done away with. The adoption of the endless rail method of conveyance would prove a fortune to the Landes, where pine forests abound, and the wood and resin which is lost for want of transport could be removed and sold to advantage.

The endless rail may also be used upon the ordinary road in places where the highways are out of repair.

THE SMALLEST STEAMBOAT IN THE WORLD.

The picture (fig. 904) shows us the _Nina_, the tiniest steamer afloat. The keel is somewhat over twelve feet in length, and about three feet wide, the depth of water ten inches. A speed of about five-and-a-half miles an hour can be obtained with a pressure of one hundred pounds. It is a twin-screw “ship” with propellers of three blades. The _Nina_ was built on the lines of the _Nautilus_, of cedar and oak, and coppered. It is stated to be a marvel of solidity and lightness. The chimney is movable, and can be lowered at pleasure if a bridge be too low. There is ample room for provisions for the occupant in a frame which can be attached to the sides or fixed astern. The boat is easily carried in sections, and can be transported easily from place to place.

The weights of the various portions are as follows:—The hull 90 lb., boiler 80 lb., engine 25 lb., machinery 20 lb.; total, 215 lb. Forty pounds of good charcoal can be packed into the sides of the boat in racks. The rudder can be so connected by wires that the feet will perform the function of steering, thus leaving the hands free to attend to the engine, so the occupant is perfectly at liberty to go where and how he pleases.

For river navigation or calm sea-steaming the _Nina_ is admirably adapted, and any one who can be stoker, steersman, and engineer, as well as passenger and crew, will enjoy a trip in such a boat. Such a steamer costs about £250, but it might be less. It may be added that the _Nina_ has uniformly behaved well, and was built by Fordham of New York.

A MECHANICAL CARRIAGE.

A distinguished _savant_ of the seventeenth century, Ozanam by name, a member of the Academy of Science, gave in 1693 a curious description of a mechanical carriage, which may perhaps be regarded as the parent of the velocipede and the bicycle. We here reproduce the engravings from Ozanam’s work and his words.

“Some years ago,” wrote the philosopher in 1693, “there may have been seen in Paris a chaise,” as in the picture, “and which a servant, by pressing alternately upon treadles” (as in the detail), “caused to progress by turning two small wheels hidden in a frame between the hinder pair of wheels of the chaise. The description I give as I received it from M. Richard, the doctor of Rochelle.

“A A is a roller attached to the box behind the vehicle, B is a pulley, over which the cord that works with the treadles passes; C and D are the treadles, with pedals, F F. The wheels, H H, being thus put in motion, the large wheels are moved, and when the hind wheels move forward, the foremost ones must advance also, and the sitter has only to guide the machine by the reins he holds attached to the guiding axle.”

THE END.

INDEX.

Aberration, Chromatic, 104.

” of sphericity, 105.

Absorption of light, 95.

Acid, Acetic, 411.

” Citric, 414.

” Formic, 415.

” Lactic, 415.

” Malic, 414.

” Oxalic, 414.

” Tannic, 414.

” Tartaric, 414.

Acoustics, Instruments for, 180.

” The science of, 166.

Actinozoa, The, 710.

Action and reaction, 35.

” Catalytic, 328.

” Electro-chemical, 220.

Adhesion of fluids, 25.

Aerolites, Meteorites or, 493.

Age, The great ice, 595.

Agricultural, Science in, 7.

Air, Composition of, 340.

” Composition of the, 45.

” As motive power, 57.

” Experiments with, 45.

” Movement by heat, 82.

” Pressure of, in bodies, 292.

” ” on mountains, 55.

” ” the, 45.

” Science in open, 6.

” Weight of the, 50.

” pump, Experiments, 45.

” ” Description, 51.

” ” Sprengel’s, 51.

Alarum lamp, A new, 760.

Albumen, 422.

Alchemists, Celebrated, 336.

Alchemy, 336.

Alcoholic thermometers, 80.

Alcohol, 419.

Alembic, The, 357.

Algæ, Mosses and, 688.

Alkali, Definition of an, 310.

Alphabets, Telegraphic, 238, 241.

Alps, Electric clouds in the, 291.

Alum, 440.

Aluminum, 393, 439.

Amber, 421.

Amebæ, The, 705.

Ammonia, Uses of, 361.

Ammonite, 18.

Ammonium, 393, 437.

” never found, 365.

Amorphous crystals, 431.

Anæsthetic, A new, 13.

Analysis of chance, 726.

” Spectrum, 145.

Anamorphoses, 135.

Anatomy of the eye, 102.

Anemones, Sea, 710.

Angles, how to measure, 474.

Animal electricity, 283.

Animals, Classifications of, 701.

” Vertebrate, etc., 700.

Annelidæ, The, 714.

Annulosa, The, 714.

Anthelion, An, 300.

Antimony, Uses of, 404, 446.

Apparatus for Botanists, 17.

” Geologists, 17.

” Mineralogists, 17.

Appliances, Astronomical, 557.

Aqua regia, 325.

Aquarium, A home-made, 9.

Aquarius constellation, 540.

Aquatic experiments, 9.

Arachnida, The, 723.

Arc, Voltaic, 223.

Archimedes, Principle of, 68.

” Story of, 68.

Areometer, Use of the, 27.

Aries, Constellation, 536.

Arsenic, 386, 446.

Artesian wells, 604.

Ascents, Celebrated balloon, 301.

Ascent, Gay-Lussac’s, 298.

Astatic galvanometer, The, 227.

Asteroids, The, 527.

Astræa, Discovery of, 528.

Astronomers, Celebrated, 468.

Astrology, Early practice of, 467.

Astronomy, Definition of, 466.

” History of, 466.

” Terms used in, 471.

Atmosphere, Composition of, 340.

” the same, 628.

Atmospheric boat, The, 452.

” electricity, 283.

Atom, Definition of an, 309.

Atomic or combining weight, 309.

” theory, The, 309.

Attraction, Capillary, 25, 64.

” Chemical, 25.

” Molecular, 65.

” of cohesion, 24.

Audiphone, The, 185.

” Uses of the, 185.

Augites, 439.

Aurora borealis, Cause of, 646.

Autophone, Principle of, 184.

” Use of the, 183.

Axis, Floral, 679.

Azimuth compass, The, 260.

Azote, 359.

Balance, Chemists’, 26.

” Hydrostatic, 26.

” Laws of, 25.

Balard, Experiments of, 27.

Ballooning, Sensational, 302.

Balloons, Accidents to, 297.

” Early ascents in, 296.

” Endeavours to steer, 306.

” Filling, 305.

” Principle of, 305.

Band, A phantom, 196.

Barium, 393.

Barometer, Aneroid, The, 53.

” Glycerine, The, 54.

” Pascal’s, 52.

” Weather forecasts, 652.

Barometers, Various, 53.

Barytes, 393, 438.

Bases, Definitions of, 310, 415.

Batteries, Different galvanic, 222.

Battery, electric, Description, 208.

Beaches, Mirage on, 18.

Bear, The Great, 542.

Bell, diving, The, described, 56.

Bernard Palissy, Saying of, 1.

Bessemer process, The, 399.

Bicyclist, A toy, 765.

Binocular vision, 141.

Biology, Meaning of, 658.

Bird, M. Tatin’s artificial, 451.

Birds, Mechanical, 449.

Blue John, 395.

” Lias, The, 586.

Boat, Atmospheric, 452.

Bores, or tidal waves, 613.

Boron, 386.

” Mineral nature of, 435.

”Boss” puzzle, The, 731.

Botanists, Apparatus for, 17.

Botany, Introduction to, 657.

Boxes, Scientific money, 745.

Breezes, Sea and land, 630.

British Isles, Date of the, 593.

Bromine, where found, 367.

Bronze Age, The, 598.

Bulb, What is a, 667.

” Wollaston’s, 91.

Bullets formed by electricity, 264.

Bunter formation, The, 585.

Buoyancy of water, The, 67.

Burglar-detector, A new, 195.

Butterflies, Capture of, 16.

Cabinets, Optical, 98.

Cadot’s clock, 752.

Cæsum, 393.

Calamine, 403.

Calcium, 393, 437.

Calculation, Machine for, 755.

Caloric, Theory of, 72.

Calyx, The, 675.

Cambrian system, 575.

Camera obscura, The, 140.

” photographic, The, 151.

Camphor, 421.

Campylometer, Construction, 750.

” Use of the, 749.

Cancer, Constellation, 538.

Candle, The burning of, 155.

Capillarity, 25.

” Description of, 64, 25.

Capillary attraction, 64, 25.

Capricornus, Constellation, 539.

Carbon, Importance of, 368.

” Mineral nature of, 435.

Carbonic acid, 343.

” Danger of, 374.

Carboniferous formation, The, 578.

Carbonization, Slow, 423.

Card, to perforate by electricity, 215.

Caseine, 422.

Castelli, Experiment of, 78.

Catalepsy, How to induce, 12.

” in fowls, 12.

Cataleptic fowl, The, 12.

Cell, A botanical, 661.

Cells, Animal, 704.

” Plant, 661.

Cellular tissues, 661.

Cementation, 398.

Centre of Gravity, 25.

” magnitude, 34.

” parallel forces, 34.

Centrifugal force, 43.

Cephalopods, 725.

Ceres, Discovery of, 528.

Chalk, Fossils of the, 589.

Chance, Analysis of, 726.

Chemical attraction, 25.

Chemistry, Early history of, 336.

” Introduction to, 307.

” Organic, 410.

” Sleight of hand and, 335.

” The science of, 22.

” without a laboratory, 313.

Children,, Simply-made toys for, 764.

” Trapeze and swing for, 763.

Chladni’s figures, 195.

Chlorine, 366.

” Uses of, 367.

Chloroform, Use of, 420.

Chlorophane, 333.

Chlorophyl, Definition of, 660.

Chromatic aberration, 104.

Chromosphere, The sun’s, 499.

Chromium, 404, 446.

Chromograph, The, 748.

Chronograph, The, 478.

Chronometers, Solar, Use of, 563.

Circles, Optical illusions with, 131.

Circulating fountain, The, 454.

Cirripeds, The, 723.

Classification of animals, 701.

” plants, 694.

Clay, Uses of, 321.

Cleavage attribute of minerals, 432.

Clepsydra, The, 479.

Climate, Differences in, 653.

” Meaning of the term, 652.

Climatology, 651.

Clock, A cosmographical, 559.

” Cadot’s, 752.

” Houdin’s, 752.

” Roberts’, 753.

Clock-lamp, A, 759.

Clocks, Ancient, 479.

” Mysterious, 752.

” Watches and, 479.

Clouds, Causes of, 634.

” Classification of, 635.

” Electricity in, 287.

” Vapour and, 634.

Coal, Formation of, 375.

Coal found in basins, 581.

” measures, Animal life of, 578.

” period, Plants of the, 80.

Cobalt, Nickle and, 401, 445.

Cock, A cataleptic, 12.

Cohesion attribute of minerals, 431.

” Attraction of, 24.

Coke ovens, 370.

Coleoptera, The, 720.

Collection of insects, 8.

Colouring of flowers, Artificial, 329.

Colours, Star, 548.

Coma, 416.

Combustion, 345.

Comets, Celebrated, 492.

” distinguished by, 491.

Commutator, The, 236.

Compass, Azumith, The, 260.

” Invention of the, 259.

” Mariners’, To make, 201.

” Ordinary form of the, 259.

Compensation in optics, 132.

Composition of the atmosphere, 340.

Conduction of electricity, 202.

Conductors, electric, List of, 210.

” Heat, 89.

Constellations, Northern, 541.

” Southern, 543.

” The chief, 536.

Copper, 401, 445.

Coral insect, The, 620.

” islands, 619.

Corals, 710.

Cords, Knots, and puzzles, 775.

Corolla, The, 675.

Cost of light, 101.

Crabs, 723.

” Hermit, 723.

Crust, The earth’s, 566.

Crustacea, The, 722.

Crystallization, Instantaneous, 319.

Crystallography, 424.

” The study of, 427.

Crystals, Definition of term, 426.

” Forms of, 427.

” Systems of, 427, _et. seq._

Cucumbers, Sea, 714.

Cups, Volta’s crown of, 220.

Curiosity, The age of, 8.

Currents, Air, winds, and, 629.

Curves, Various sound, 176.

Cyanogen, 378.

Daguerreotypes described, 152.

Dark spot, The, 134.

Dazzling top, The, 128.

Dead Sea, Drowning in the, 67.

Decomposition, 423.

Definition of physics, 22.

Definitions, Scientific, 4.

Density, Laws about, 24.

Despatch, The pneumatic, 57.

Devonian system, 576.

Dew, Hail and, 641.

Diamonds, Cutting of, 369.

Dip, Magnetic, 256.

Discharges, Electric, 214.

Discoveries, Astronomical, 468.

Discs, Rotating use of, 108.

Distances, Measurement of, 482.

Distillation, Sublimation and, 86.

Dogs, New work for, 758.

Double stars, List of, 547.

Dress, Boyton’s swimming, 460.

Drops, Prince Rupert’s, 81.

Drummond light, The, 160.

Dunes, History of the, 615.

Dyes, Hair, 326.

Ear, Anatomy of the, 166.

Earth, Constitution of the, 568.

” Crust of the, 566.

” Facts about the, 508.

” Formation of the, 566.

” Form of the, 504.

” Latitude and longitude of, 504.

” Motion of the, 504.

” Rate of motion of the, 504.

” Stoppage of the, 507.

” Track of the, 506.

Earthquakes, Motion of, 623.

” Volcanoes and, 620.

Ebullition, 83.

” Temperature for, 83.

Echo, Causes of, 171.

” Definition of an, 171.

Eclipses, Causes of, 518.

” Lunar, 519.

” Solar, 519.

Ecliptic, The, 497.

Egg, electric, The, 214.

Elasticity, Motion by, 36.

Electric egg, The, 214.

” light, How to produce, 265.

” machine, To make an, 207.

” pen, The, 248.

” toys, 279.

Electricity a mystery, 197.

” Animal and other, 282.

” Conduction of, 202.

” decomposes water, 226.

” Derivation of, 197.

” Domestic lighting by, 271.

” in clouds, 287.

” in medicine, 230.

” Negative and positive, 203.

” Novel applications of, 250.

” not to be played with, 205.

” Static and dynamic, 209.

” Velocity of, 212.

Electro-magnetism, 255, 260.

Electro-motograph, The, 262.

Electroplating, 227.

Electrotyping, 229.

Electrodes, Poles or, 221.

Electrolysis, 226.

Electrometer, Torsion, The, 209.

Electrophorus, How to make, 198.

” Peiffer’s, 279.

Electroscope, To make an, 206.

Elements, Definition of the, 307.

” Electrical relation, 410.

” Phial of the four, 47.

” Table of the, 308.

Emulsion process, The, 153.

Encrinites, The, 713.

Endless rails, Use of, 771.

Endogens, Enogens and, 665.

Endosmose, 663, 692.

Energy changed into heat, 91.

Entozoa, The, 716.

Eocene formation, The, 591.

Epidermis of plants, 664.

Epsom salts, 395.

Equator, Magnetic, 256.

Equilibrium, Laws of, 28.

Equatorial, The, 478.

Equinoctial, The, 495.

Equinoxes, Precession of the, 497.

” Solstices and, 496.

Eruption, Signs of an, 621.

Estimation, ocular, Illusions of, 116.

Ether, 419.

” Stillness of, 168.

” The nature of, 93.

Eudrometer, Use of the, 353.

Europe, Geological date of, 593.

Eusthenes, Experiment by, 38.

Evaporation defined, 83.

” Laws of, 84.

Exogens, Endogens and, 665.

Experiments, Some of Edison’s, 269.

Eye, Accommodation in the, 103.

” Light in the, 142.

” The, an optical instrument, 102.

Faculae, what they are, 498.

Fata Morgana, The, 649.

Felspars, 442.

Fertilization of plants, 682.

Fibrine, 422.

Figures, Chladni’s, 195.

Fiords, Norwegian, 615.

Fire, Green, 393.

” Red, 395.

Fish, A fossil, 577.

” Electric, 284.

” Magic, 281.

” New swimming toy, 765.

” Star, 713.

Fishes, how they breathe, 358.

Fixed stars, The, 535.

Flames, Sensitive, 195.

” Singing, 195.

Flowers, artificial, Colouring of, 329.

” what are they, 675.

Fluorine, 368.

Flying, Earliest attempts at, 294.

Foraminifera, The, 705.

Force, Centrifugal, 43.

” Definition of a, 4.

Forces, Natural, 22.

” Parallel centre of, 34.

Formation, Carboniferous, 578.

” Eocene, 591.

” Jurassic, 586.

” Lias, 586.

” Maestricht, 590.

” Miocene, 593.

” Oolite, 586.

” Permian, 582.

” Trias, 585.

” Wealden, 588.

Fountain, Circulating, 453.

Fracture, attribute of minerals, 433.

Franklin, Experiments of, 205.

Fraunhofer, Discovery of, 143.

Freezing machinery, 363.

” mixtures, 89.

Friction, Definition of, 40.

” Inertia and, 35, et sq.

Frogs, Electrified, 217.

” Tree, 11.

Fruit, Definition of, 684.

” How formed, 683.

Fruits produced by one carpel, 685.

” ” several, 685.

Fulgarites, 644.

Fungi, 690.

” Destructive, 690.

” Edible, 691.

” Propagation of the, 692.

Fusee, The, 481.

Fusion, Definition of, 88.

Future ages, The, 599.

Galaxy, The, 553.

Galena, Use of, 401.

Galileo, Tube of, 148.

Galleries, Whispering, 172.

Galvani, defeated by Volta, 218.

” Discovery of, 217.

Galvanometer, Astatic, 227.

” Pungent, 227.

” , Use of the, 223.

Galvanoscope, The, 227.

Game, The needle, 729.

Games, Mathematical, 726.

Garnets, Mineral nature of, 442.

Gas, Coal, 375.

” companies’ profits, 377.

” Definition of, 4.

” harmonicon, The, 351.

” Laughing, 361.

” Marsh, 347.

Gases, Liquids and, 44.

Gauges, Rain, 638.

Gazogene, Use of the, 373.

Gemini, Constellation, 537.

Gems, The precious, 443.

Generation of heat, 77.

Generator, gramme, The, 268.

Geography, Geology and, 564.

” Physical, 601.

” Sources of, 603.

Geologists, Apparatus for, 17.

Geology, what it teaches, 565.

Germany, experiment in, 13.

Geysers, The, 605.

” Theory of the, 84.

Ghost, Pepper’s, 138.

” stories, 161.

Ghosts, Explanations about, 161.

” substantial, 142.

Gilding, Processes of, 407.

Glacial period, Cause of the, 595.

” The, 595.

Glaciers, Ice-rivers and, 606.

Glass, Facts about, 384.

” perforated by electricity, 215.

Glauber’s salt, 393.

Globe, Motion of the, 504.

” Spherical form of the, 504.

Globes, terrestrial, Use of, 562.

Gold, Nuggets of, 407, 447.

” resists acid, 325.

” the king of metals, 325.

Goniometer, Use of the, 431.

Gramme generator, The, 268.

Grapes, method of preserving, 768.

Grapes, Room for preserving, 768.

Graphite, Plumbago or, 370.

Gravitation, Force of, 4, 486.

” Laws of, 2.

Gravity, Centre of, 25.

” less in the air, 24.

” same in all bodies, 24.

Green fire, 393.

Grit, Millstone, 581.

Grotto del Cave, The, 374.

Gulf Stream, The, 618.

Gum, 418.

Gymnotus, Electricity of the, 284.

Gyroscope, Principle of the, 277.

” The, 742.

” The electric, 743.

Hail, Dew and, 641.

Halos, Lunar, 648.

Harmonograph, Construction, 175.

Havre, Mirage at, 19.

Heat, a series of vibrations, 74.

” Absorption of, 75.

” Conduction of, 89.

” Definition of, 72.

” Development of, 77.

” Expansion by, 81, 82.

” Generation of, 77.

” How to study, 75.

” Latent, 89.

” light and, Connection of, 94.

” Mechanical equivalents, 74.

” Material theory of, 72.

” produces changes of state, 89.

” Radiant, 90.

” Reflection and refraction, 92.

” Science of, 72.

” Sources of, 77.

” Specific, 88.

” spectrum, The, 146.

” the movement of particles, 91.

” Theory of, 72.

History, Natural, 4.

Holland, Sailing on land in, 463.

Home-made aquarium, A, 9.

Hope, Mathematical, 727.

” Moral, 727.

Horn, Alexander’s, 183.

Hornblend, 439.

Horoscopes, Early study of, 467.

Horses, Electric government of, 250.

Houdin’s clock, 752.

Household, Scientific objects for, 747.

Hydraulic Lift, The, 71.

” press, The, 61.

Hydraulics, 70.

Hydrogen, Apparatus for, 322.

” Bubbles of, 351.

” How to generate, 350.

Hydrometers, Table of, 420.

Hydrophilus, The, 10.

Hydrostatics, Principles of, 61.

Hydrozoa, The, 708.

Hymenoptera, The, 721.

Hypnotism, 13.

Ice, How to freeze, 76.

” The age of, 595.

Ice-rivers, Glaciers and, 606.

Ice-yachts, Canadian, 463.

Iceland, Geysers in, 605.

Igneous rocks, 571.

Illusions, Optical, 116.

” ” More about, 129.

Images, Accidental, 112.

Implements, Neolithic, 598.

” Palæolithic, 598.

Inclination, Magnetic, 256.

Indicator, Use of the celestial, 558.

Inertia, Definition of, 5.

” Experiments in, 37.

” Friction and, 35, _et sq._

” Laws of, 35.

Inflorescence, 679.

” Varieties of, 680.

Infusoria, Divisions of the, 707.

” How to capture, 15.

” Origin of, 707.

” Study of, 7.

Inks, how made, 414.

Insects, 717.

” Anatomy of, 717.

” Collection of, 8.

” Eyes of, 718.

” Feet of, 718.

” Orders of, 720.

” Palace for, 10.

” Preservation of, 8.

” Transformations of, 719.

Insulators, electric, List of, 210.

Integrator, Boys’ mechanical, 264.

Intensity of sound, 171.

Iodine, 368.

Iron age, The, 598.

” Bar, 397.

” Mineral nature of, 443.

” Ores of, 444.

” Pig or cast, 397.

” Pyrophoric, 322.

” unites with oxygen, 321.

” whence obtained, 396.

Irradiation, Laws of, 106.

Islands, Coralline, 619.

Isoclinic lines, 257.

Isodynamic lines, 257.

Isogenic lines, 257.

Jar, Leyden, Home-made, 199.

Jardin, The, near Chamouni, 607.

Jelly-fish, 709,.

Jersey, Mirage in, 19.

Juggling, Balance experiments, 31.

Juno, Discovery of, 528.

Jupiter, Appearance of, 530.

” Moons of, 529.

” The planet, 528.

Jurassic formation, The, 586.

Keuper formation, The, 585.

Kinetic theory, The, 72.

Kite, A new, 448.

” Franklin’s, 286.

Knots and cords, Puzzle of, 775.

Laboratory, Chemistry without, 313.

Lactoscope, The, 157.

Ladd, Lontin and, 275.

Lakes, 627.

Lamp, A good petroleum, 761.

” A new alarum, 760.

” Dobereiner’s, 408.

” Gay-Lussac’s, 327.

” The Edison, 269.

” The safety, 347.

” The Swan, 271.

Land, Sailing on, 463.

” Water and, 603.

Lantern, Magic, 158.

Lapis-lazuli, 442.

Latent heat, 89.

Latex, what it is, 663.

Latitude, Longitude and, 505.

Laughing gas, 361.

Laurentian system, The, 573.

Lead, 401, 446.

” Crystallization of, 323.

Leaning, Laws concerning, 33.

” towers, Laws of, 33.

Leaves, Anatomy of, 671.

” Arrangement of, 673.

” The, 670.

” Varieties of, 671.

” Various, 150.

Leech, The, 714.

Lenses, Description of various, 150.

Leo, Constellation, 538.

Lepidoptera, The, 721.

Leyden jar, To make a, 199.

Lias, The, 586.

Libra, Constellation, 539.

Lichens, 689.

Lift, Hydraulic, 71.

Light, a vibratory motion, 93.

” Absorption of, 95.

” and its sources, 93.

” Cost of, 101.

” Decomposition of, 143.

” Definition of, 93.

Lightning, Different kinds of, 289.

Light distributed in rays, 94.

” electric, How to produce, 265.

” ” First discovery of, 221.

” heat and, Connection of, 94.

” in the eye, 142.

” of an electric spark, 119.

” oxy-hydrogen, The, 160.

” Polarization of, 155.

” producer of life, 660.

” Reflection of, 95.

” Refraction of, 96.

” Velocity of, 94.

” what made up of, 143.

” Zodiacal, 500.

Lightning, Forked and sheet, 289.

” Colour of, 288.

Lights, Bengal, how made, 404.

” Comparison of, 99.

Lime, Salts of, 393, 437.

Lines, Isoclinic, 257.

” Isodynamic, 257.

” Isogonic, 257.

” Isothermal, 653.

” oblique, Influence of, 121.

Linnæan system, The, 695.

Liquids, Definition of, 4.

” Displacement of, 69.

” Gases and, 44.

Lithium, 393.

Longitude, Latitude and, 505.

Lontin, Ladd and, 275.

Ludion, The, 57.

Luminous paint, 160.

” surfaces, Laws of, 107.

Machine, electric, To make an, 207.

” Tree-felling, 767.

” Writing, 246.

Machines, Electro-magnetic, 272.

Maestricht formation, The, 590.

Magic squares, 732.

” top, The, 740.

Magnesian limestone, The, 583.

Magnesium, 395, 439.

Magnet, A natural, 231.

” Definition of a, 231.

Magnetic dip, The, 256.

” inclination, 256.

Magnetism, Electro, 255.

” Terrestrial, 645.

Magnetization, 232.

Magnets in ancient times, 254.

Magnitude, Centre of, 34.

Man, cave, The, 598.

” during the Glacial Period, 597.

” prehistoric, 597.

” river-drift, The, 598.

Manganese, 400, 445.

Mars, Moons round, 526.

” The planet, 523.

Mathematical games, 726.

Matter, Definition of, 4.

Medullary rays, The, 669.

Medusæ, The, 709.

” Phosphorescence of, 740.

Megaphone, Mr. Edison’s, 183.

Membrane tympani, The, 166.

Menagerie for insects, 10.

Menisques in a barometer, 65.

Mercury, All about, 521.

” Fulminating, 420.

” Uses of, 405, 446.

Mesozoic period, The, 584.

Metals, Characteristics of, 388.

” Classification of, 389, 409.

” Common and precious, 320.

” in the spectroscope, 146.

” Noble, 405.

” Specific gravity of, 389.

” what they are, 388.

Meteorites, aerolites, or, 493.

Meteorology, 628.

” Phenomena of, 20.

Meteors, what are they? 490.

Mica, 443.

Microscope, Invention of the, 149.

” periscopic, The, 150.

” The spectrum, 147.

Microscopes, Reflecting, 150.

Milk, Constituents of, 422.

” Sugar of, 423.

Milky way, The, 553.

Millstone grit, 581.

Mineralogists, Apparatus for, 17.

Mineralogy, Crystallography, 424.

Mineral waters, 372.

Minerals, Amorphous, 431.

” Classification of, 424, 425.

” Definition of the term, 424.

” Synoptical table of the, 435.

Miocene formation, The, 593.

Mirage at Havre, 19.

” Cause of, 649.

” in Jersey, 19.

” on beaches, 18.

Mirrors, Remarks on, 95.

Mistral, The, 631.

Mixtures, Freezing, 89.

Molecule, Definition of a, 309.

Molluscs, 724.

Money-boxes, Scientific, 745.

Montgolfier, Discovery of, 2.

” Early balloons of, 295.

Monsoon, The, 630.

Moon, Description of the, 510.

” Eclipses of the, 519.

” Influences of on weather, 652.

” its influence on the tides, 517.

” Motion of the, 513.

” Phases of the, 515.

” Rate of progression of the, 513.

” Superstitions concerning, 510, 513.

” Surface of the, 511.

” Planetary, 489.

Morphine, 416.

Morse system, The, 241.

Morse’s telegraph, 233.

Mosses, Algæ and, 688.

Motion, Causes of, 40.

” Definition of, 40.

” Perpetual, 41.

Mould, Vegetable, 690.

Mountain strata, Contortion of, 625.

” What is a, 624.

Mountains, Causes of, 624.

” Slopes of, 625.

Movements, Synthesis of, 124.

Multiplier, First use of the, 232.

Mural circle, The, 478.

Musical pitch, 193.

Muslin, Incombustible, 313.

Myriapoda, The, 716.

Natural History, 4.

” Philosophy, 4.

” system, The, 699.

Nature, Balance of, 617.

” Forces of, 22.

” Need for knowing about, 3.

” Nothing mute in, 21.

” Smooth polish of, 14.

” Phenomena of, 3.

” what it is, 2.

Near-sightedness, 140.

Nebulæ, 551.

Needle, Game of the, 729.

” The magnetic, 231.

” machine, The, 238.

Negative and positive electricity, 202.

Neptune, The planet, 534.

Nichol’s prism, 156.

Nicholson’s classes of plants, 702.

Nickel, cobalt and, 401, 445.

Nicotine, 416.

_Nina_, The, 773.

Nitrogen, 359.

” Compounds of, 359.

” Monoxide, 361.

Nitrogenous substances, 422.

Nodal points, The, 194.

Nodes of sound waves, 169.

Noise distinguished from sound, 167.

Nomenclature, Astronomical, 471.

Normandy, A trip in, 6.

Object, A natural, 3.

Oils, Fats and, 421.

”Old Red” a fresh-water deposit, 577.

Oolite formation, The, 586.

Opium, 416.

Optical cabinets, 98.

Optics, The science of, 93.

Organic chemistry, 410.

Orion constellation, 544.

Orthoptera, The, 721.

Oxidation, 349.

Oxygen, Discovery of, 348.

” consumed by breathing, 342.

” How to obtain, 348.

Oysters, Light from shells of, 160.

Ozone, Use of, 344.

Paint, Luminous, 160.

Palace, Insects, 10.

Palæozoic systems, 573.

Pallas, Discovery of, 528.

Paper wheel toy, 764.

Parachutes, Descents by, 304.

Parallax, Explanation of, 484.

” Illustrations of, 483.

” Use of, 485.

Para-magnetic and dia-magnetic, 258.

Paraselenæ, Cause of, 648.

Paris, Great snowfall in, 20.

Pedometer, The, 756.

Peiffer’s electrophorus, 279.

Pen, electric, The, 248.

Pencil, Edison’s Pneumatic, 454.

Pendulum, Description of the, 42.

” The, 481.

” Variations in the, 42.

Period, The Glacial, 595.

Permian formation, The, 582.

” ” Fauna of, 582.

Phantom band, A, 196.

Pharaoh’s serpents, 315.

Phases of the Moon, 515.

Phenakistoscope, The, 110, 121.

Phenomena, Atmospheric, 642.

” Chemical, 22.

” Meteorological, 20.

” Nature, 3.

” of contrast, 112, 113.

” Physical, 22.

Phial of the four elements, 47.

Philosophy, Natural, 4.

Phonograph, Edison’s, 190.

Phosphorescence, 331.

Phosphorus, Bologna, 333.

” how obtained, 381.

Photography, Camera for, 151.

” Instantaneous, 153.

Photometers, 101.

Photometry, 101.

Photophone, The, 155.

Photosphere, The, 499.

Phraseology, Chemical, 338.

Physics, Meaning of, 22.

” Mechanical, 31.

Pile, A microscopic, 200.

” hermetic, The, 283.

” Volta’s first, 219.

” Zamboni, 221.

Pins, scarf, Electrical, 281.

Pisces, Constellation, 540.

Pistil, The, 678.

Pistils, Use of, 665.

Pitch, Musical, 193.

Plains, 626.

Planet, The giant, 528.

Planets, Comparative sizes of, 487.

” List of the, 487.

” Minor, 489, 527.

” Moons of the, 489.

Plant, Definition of a, 661.

Plants, Classification of, 694.

” Flowering, 664.

” Growth of, 665.

” Monœcious, 681.

” Non-flowering, 686.

” Similarity of, to animals, 658.

” Structure of, 661.

Plateaus, Tablelands or, 626.

Plating, Electro, 227.

Platinum, All about, 327.

” Uses of, 408, 447.

Plumbago, Graphite or, 370.

Plutonic rocks, The, 601.

Pneumatic despatch, The, 57.

Polaris, The star, 542.

Polarization of light, 155.

Polarizer, Use of a, 156.

Poles, Electrodes or, 221.

Pompeii, Paintings at, 121.

Porcelain, Manufacture of, 441.

Porosity, Definition of, 5.

Positive and negative electricity, 202.

Portuguese man-of-war, The, 709.

Potassium, 390, 437.

” Compounds of, 391.

Praxinoscope, The, 110, 123.

” theatre, The, 126.

Prehistoric man, 597.

Preservation of insects, 8.

Press, Hydraulic, 61.

Pressure, Fluid application of, 63.

” on the ocean bed, 616.

Prism, Nichols’, 156.

Probabilities, Science of, 726.

Protoplasm, Definition of, 659.

Protozoa, Definition of, 704.

Protractor, Use of the, 475.

Pump, The common, 57.

Punctum cæcum, The, 134.

Puzzle, The ”Boss,” 731.

Pyrites, Crystallized, 18.

” Iron, 444.

Pyrometer, The, 91.

Quadrant, Use of the simple, 476.

Quarry, Derivation of the term, 427.

Quartz, Varieties of, 436.

Quicksilver. _See_ Mercury.

Quinine, 416.

Radiant heat, 90.

Rain, Causes of, 637.

” Distribution of, 637.

” Measurement of, 638.

” water, The, 71.

River-beds, Slope of, 626.

Rainbow, The, 647.

Rays, Medullar, 669.

Reaction, Action and, 35.

Recreation, Science and, 1.

Red fire, 395.

Reflection of heat, 92.

” light, 95.

” sound, 171.

Refraction of heat, 92.

Reaction of, light, 96.

” sound, 171.

Refractions, Table of, 479.

Reptiles, The age of, 585.

Repulsion in air-particles, 48.

Ruins, 421.

Rest, No absolute, 40.

Rhizome, Definition of, 667.

Rhone, Colours of the, 570.

Robert’s clock, 753.

Robin’s spectres, 138.

Rocks, Acidic, 602.

” Basic, 602.

” Igneous, 571, 601.

” Plutonic, 601.

” Sedimentary, 570.

” Volcanic, 601.

Roots, Various, 666.

Rubidium, 393.

Sagittarius, Constellation, 539.

Sailing on railroads, 465.

Salt, Glauber’s, 393.

” Epsom, 395.

” what meant by in chemistry, 311.

Sandstone, Old Red, 576.

” Upper Red, 585.

Sassoline, Boron or, 435.

Satellites, Planetary, 489.

Saturn, Rings of, 532.

” Satellites of, 532.

” The planet, 532.

” Tree of, 323.

Sawing, Machine for, 767.

Scale, diagonal, Use of the, 477.

Scarf-pins, Electrical, 281.

Scavengers, Nature’s, 713.

Scenograph, Description, 153.

Scheele, Apparatus used by, 28.

Science and Recreation, 1.

” Definitions of, 1-5.

” Domestic economy and, 757.

” in the open air, 6.

Scorpio, Constellation, 539.

Sea, At the bottom of the, 615.

” Saltness of the, 610.

” The, 610.

” anemones, 710.

” bed, Irregularity of the, 617.

” cucumbers, 714.

” urchins, 712.

” water, Buoyancy of, 67.

” ” Composition of, 610.

Sealing-wax, Experiments with, 197.

Seasons, Recurrence of the, 507.

Sedimentary rocks, 570.

Selenium, 386.

” Mineral nature of, 435.

Selenography, 510 _et sq._

Semaphore, The, 232.

Serpents, Pharaoh’s, 315.

Sewing-machines, Motive power, 758.

Shadows, comic, 158.

Shot, how made, 403.

Signalling, 183.

Silicon, Silica and, 383, 436.

Silurian system, 575.

Silver dissolved by nitric acid, 326.

” how obtained, 406, 447.

” Uses of, 406.

Simoon, The, 631.

Sky, How to read the, 555.

” why blue, 647.

Sleet, Cause of, 640.

Sleight of hand, Chemistry and, 335.

Smelting, Melting and, 396.

Snow, Causes of, 639.

” Great falls of, 20.

” what it is, 639.

Soap, how made, 391.

Soap-bubbles, Notes on, 98.

Sodium, 392, 437.

” Experiments with, 317.

Solar chronometers, 563.

” spectrum, The, 143.

Solid, Definition of, 4.

Solitaire, explanation of puzzles, 736.

” The game of, 735.

Solstices, Equinoxes and, 496.

Sound impossible without air, 163.

” Intensity of, 171.

” Reflection of, 171.

” Refraction of, 171.

” transmitted by solids, 174.

” Velocity of, 169.

” Velocity of, varies, 170.

” what it is, 167.

” whence it arises, 167.

Sound-waves, Nodes of, 169.

” to see, 173.

Sounds, musical and unmusical, 167.

Sources of heat, 77.

Space, what it is, 4.

Spar, Derbyshire, 395.

Spark, Electric duration of, 213.

” Light of an electric, 119.

Speaking tubes, 172.

Specific gravity, 68.

” Huxley’s definition of, 70.

” of metals, 389.

Specific heat, 88.

Spectacles, Different glasses for, 150.

Spectra, Composition of, 147.

” ocular, 143.

Spectral illusions, 161.

Spectre, a visible, 161.

” of the Brocken, The, 650.

Spectres, Impalpable, 126.

” M. Robin’s, 138.

Spectroscope, Discovery of the, 145.

” Uses of the, 145.

Spectroscopy, Science of, 145.

Spectrum analysis, 145.

” heat, 146.

” solar, 143.

Sphericity, Aberration of, 105.

Spider tribe, The, 723.

Sponges, Nature of, 706.

” Reproduction of, 706.

Spots, Sun, 498.

Springs, Causes of, 604.

Squares, Magic, 731.

Stamens, The, 677.

” Uses of, 665.

Starch, Notes about, 417.

Star, pole, The, 494.

Star-fish, 713.

Stars, Clusters of, 551.

” Colours of the, 548.

” Distance of the, 544.

” Double and multiple, 546.

” Falling, 490.

” Fixed, 535.

” Lost, 550.

” Magnitude of the, 554.

” Motions of, 535.

” New, 550.

” Number of the, 536.

” Radiating form of, 105.

” Showers of, 491.

State, Changes of, produced by heat, 89.

Static electricity, 209.

Steam, Definition of, 91.

” Tree-felling by, 766.

Steamer, The smallest, 773.

Stem, Parts of the, 667.

” The, 667.

” Varieties of the, 667.

Stems, Tree, 668.

Stereoscope, Principle of the, 141.

” Reflecting, 141.

” Refracting, The, 141.

Stone, Pudding, 568.

Stories, Ghost, 161.

Strata, List of geological, 573.

Strepsiptera, The, 721.

Strings, Vibration of, 170.

Strontium, 395, 438.

Strontium, Luminous sulphates, 333.

Structure of plants, 661.

Strychnine, 416.

Sublimation and distillation, 86.

Substances, Indifferent, 417.

Substances, Nitrogenous, 422.

Sucker, The school-boy’s, 48.

Sugar, Refining of, 418.

Sulphur, Mineral, 435.

” Uses of, 379.

Sun, Density of the, 503.

” Distance of the, 503.

” Eclipses of the, 519.

” Form of the, 498.

” Motion of the, 496.

” Power of the, 503.

” Spots on the, 498.

” Volume of the, 503.

Suns, mock, Cause of, 648.

Sunset, Colours of the, 655.

Surfaces, luminous, Laws of, 107.

Swan lamps, The, 271.

Swimming, New apparatus for, 458.

Swing, Simple child’s, 763.

Symbols, Chemical table of, 308.

Synthesis of movements, 125.

Syphon recorder, Thomson’s, 244.

Syren, The, 194.

Syringes, An effect of atmospheric pressure, 63.

System, Cambrian, 575.

” Coal, 578.

” Devonian, 576.

” Laurentian, 573.

” Silurian, 575.

” The Solar, 487.

Systems, Palæozoic, 573.

Tablelands, Plateaus or, 626.

Tadpoles in aquaria, 10.

Talking head, How to work, 135.

Tangent galvanometer, The, 227.

Tanning, 414.

Tanning, Process of, 414.

Tap, A new kind of, 762.

Tape-worms, 716.

Tar, Uses of, 378.

Taurus, Constellation, 537.

Telegraph, Automatic, 243.

” electric, Discovery of, 232.

” ” Ordinary form of, 234.

Telegraphic system, New, 244.

Telegraphs, Early, 232.

Telegraphy, Practical, 239.

” Submarine, 243.

Telephone, Description of the, 186.

” Invention of the, 186.

Telescope, Achromatic, 149.

” Description of the, 147.

” Divided, explained, 135.

” Introduction of the, 469.

” reflector, The, 149.

Telescopes, 149.

Tellurium, 386.

Terminations, Chemical, 337.

Tertiary period, The, 591.

Thaumatrope, The, 110, 121.

Theatre, The praxinoscope, 126.

Theory, atomic, The, 309.

Thermo-dynamics, Definition of, 73.

Thermometer, How to make a, 79.

” Invention of the, 78.

Thermometers, Alcoholic, 80.

Thunder, Causes of, 291.

Thunderstorms, Precautions, 283.

Tides, Ebb and flow of, 612.

” Influence of the moon, 517.

” Science of the, 614.

Time, Ancient measurements of, 479.

” Equation of, 482.

” Sidereal, 478.

Tin, Crystallization of, 324.

” Uses of, 403, 446.

Tissues, Cellular and vascular, 661.

Top, The dazzling, 128.

” The magic, 740.

Topophone, Description of the, 180.

” Invention of the, 180.

Tops, Chromatic, 109.

” in optical physiology, 108.

Torpedo, Electricity of the, 285.

Torsion electrometer, The, 209.

Towers, leaning, Laws of, 33.

Toys, Electric, 279.

” Simple, 764.

Tramways, Electric, 272.

Transit, Curious modes of, 770.

” instrument, How to use, 477.

Trapeze, Simple home-made, 762.

Tree-felling, Steam power for, 766.

” frogs, 11.

Trias, The, 585.

” Upper and lower, 585.

Trolly-sailing, 465.

Trumpets, Speaking, 172.

Tube, Galileo’s, 148.

Tube well, The, 455.

Tuber, Definition of the, 667.

Tubes, Speaking, 172.

Tuning-fork, The, 193.

Type casting, 405.

” metal, 404.

Union, Chemical, involves heat, 311.

Uranus, The planet, 533.

Vacuum, Torricellian, 51.

Vanessa algina, 16.

Vapour, Clouds and, 634.

” what it is, 629.

Variations of the compass, 257.

Varnishes, 421.

Vascular tissues, 661.

Vehicle, A new two-wheeled, 770.

Velocipede, New water, 461.

Velocipedes, Ancient, 775.

Velocity, Acceleration of, 41.

” Definition of, 23.

” Facts about, 23.

” of Electricity, 212.

” of light, 94.

” Retarded, 41.

Ventilation, Notes on, 344.

Venus, The planet, 522.

Vessels, connected, Laws of, 62.

Vesta, Discovery of, 528.

Views, Dissolving, 160.

Vinegar, how prepared, 418.

Virgo, Constellation, 538.

Vision, Binocular, 141.

” Definition of, 103.

” Field of, 140.

” The eye and, 140.

Vivaria, 16.

Volcanic rocks, The, 601.

Volcanoes, Earthquakes and, 620.

” Formation of new, 623.

” Number of, 621.

Voltaic arc, The, 223.

Volume, Weight and, 59.

Waste, none in nature, 341.

Watches, Clocks and, 480.

Water a compound body, 353.

” a form of matter, 59.

” Action of, in Geography, 608.

” All about, 59.

” as ice, 355.

” as steam, 355.

” Buoyancy of, 67.

” Chemistry of, 352.

” decomposed by electricity, 226.

” Distillation of, 356.

” Effects of heat on, 82.

” Evaporation of, 7.

” freezing by evaporation, 85.

” Fresh, in the sea, 611.

” hot, grows lighter, 81.

” Land and, 603.

” Mineral, 372.

” Petrification of, 357.

” Pressure of, 60.

” Sea, composition of, 610.

” Spring, 353.

” sustained by air, 59.

” The force of, 60.

” the unit of specific gravity, 70.

Water-press, The, 61.

Water-ram, The, 71.

Waterspout, Cause of the, 643.

Waterspouts, How to destroy, 643.

Water-wheels, 71.

Waves, Height of the, 613.

” Hurricane, 613.

” Movement of the, 612.

” Standing and progressive, 169.

” Tidal, 613.

Way, Milky, 553.

Wealden formations, The, 588.

” ” Fauna of, 589.

” ” Flora of, 589.

Weather, Danger of forecasting, 655.

” forecasts, 651.

” indications, 656.

” Rules for prophesying, 656.

Weather-glass, The, 53.

Weight, Combining or atomic, 309.

” Definition of, 22.

Well tube, The, 455.

Wells, Artesian, 604.

” Gas, 606.

” Instantaneous, 457.

” Oil, 606.

Wheatstone’s telegraph, 242.

Whispering galleries, 172.

Wind, Pressure of the, 632.

” Use of the, 633.

Wind, Velocity of the, 630.

Windows, Double, 757.

Winds, Air currents and, 629.

” Cause of, 629.

” List of local, 631.

” Trade, 630.

Wine, Spirits of, 418.

Wire-drawing, 398.

Wollaston’s bulb, 91.

World, Study of the, 1.

Worms, The, 714.

Writing machine, The, 246.

Wings, Best form for, 450.

Yachts, Canadian ice, 463.

” Double sailing, 462.

Yellow spot, The, 140.

Zamboni pile, 221.

Zeolites, 440.

Zinc, Use of, 403, 446.

Zodiac, Signs of the, 471.

Zodiacal light, The, 500.

Zoology, Definition of, 700.

Zootrope, The, 121.

* * * * *

Transcriber’s Notes

Obvious typographical errors have been silently corrected but variations in hyphenation and all other spelling and punctuation remains unchanged.

Italics are represented thus _italic_ and bold thus =bold=.

The following corrections have been made:

Réamur has been corrected to Réaumur throughout.

Page 94 “There are seven primary colours in the sunlight, which is white. These can be divided or “dispersed,” and the shortest rays of the spectrum are found to be red, the longest violet.” has been corrected to longest red and shortest violet.

Page 109. “If, for instance, we place on a disc covered with blue and red sectors of equal size, a black disc, of which the sectors are alternately filled in or empty, the disc, as it turns round, will appear blue if the black sectors of the upper disc exactly cover the [red] sectors of the lower disc; and it appears red, if, on the contrary, the blue sectors are covered with the black;” [red] has been added.

Page 238. The footnote Monvel’s “Course of Physics.” appears, but there is no reference to it in the text.

Page 533. The time of revolution of Saturn’s Moons was given in d. h. sec., this has been corrected to d. h. min.