The Botanic Garden Volume I Part 16

Discovery of fire. Tools of steel. Forests subdued. Quant.i.ty of food increased by cookery 212

Medusa originally an hieroglyphic of divine wisdom 218

Cause of explosions from combined heat. Heat given out from air in respiration. Oxygene looses less heat when converted into nitrous acid than in any other of its combinations 226

Sparks from the collision of flints are electric. From the collision of flint and steel are from the combustion of the steel 229

Gunpowder described by Bacon. Its power. Should be lighted in the centre. A new kind of it. Levels the weak and strong 242

Steam-engine invented by Savery. Improved by Newcomen. Perfected by Watt and Boulton 254

Divine benevolence. The parts of nature not of equal excellence 278

Mr. Boulton's steam-engine for the purpose of coining would save many lives from the executioner 281

Labours of Hercules of great antiquity. Pillars of Hercules. Surface of the Mediteranean lower than the Atlantic. Abyla and Calpe. Flood of Deucalion 297

Acc.u.mulation of electricity not from friction 335

Mr. Bennet's sensible electrometer 345

Halo of saints is pictorial language 358

We have a sense adapted to perceive heat but not electricity 365

Paralytic limbs move by electric influence 367

Death of Professor Richman by electricity 373

Lightning drawn from the clouds. How to be safe in thunder storms 383

Animal heat from air in respiration. Perpetual necessity of respiration.

Spirit of animation perpetually renewed 401

Cupid rises from the egg of night. Mrs. Cosway's painting of this subject 413

Western-winds. Their origin. Warmer than south-winds. Produce a thaw 430

Water expands in freezing. Destroys succulent plants, not resinous ones.

Trees in valleys more liable to injury. Fig-trees bent to the ground in winter 439

Buds and bulbs are the winter cradle of the plant. Defended from frost and from insects. Tulip produces one flower-bulb and several leaf-bulbs, and perishes. 460

Matter of heat is different from light. Vegetables blanched by exclusion of light. Turn the upper surface of their leaves to the light. Water decomposed as it escapes from their pores. Hence vegetables purify air in the day time only. 462

Electricity forwards the growth of plants. Silk-worms electrised spin sooner. Water decomposed in vegetables, and by electricity 463

Sympathetic inks which appear by heat, and disappear in the cold. Made from cobalt 487

Star in Ca.s.siope's chair 515

Ice-islands 100 fathoms deep. Sea-ice more difficult of solution. Ice evaporates producing great cold. Ice-islands increase. Should be navigated into southern climates. Some ice-islands have floated southwards 60 miles long. Steam attending them in warm climates 529

Monsoon cools the sands of Abyssinia 547

Ascending vapours are electrised plus, as appears from an experiment of Mr. Bennet. Electricity supports vapour in clouds. Thunder showers from combination of inflammable and vital airs 553

CANTO II.

Solar volcanos a.n.a.logous to terrestrial and lunar ones. Spots of the sun are excavations 14

Spherical form of the earth. Ocean from condensed vapour. Character of Mr. Whitehurst 17

Granite the oldest part of the earth. Then limestone. And lastly, clay, iron, coal, sandstone. Three great concentric divisions of the globe 35

Formation of primeval islands before the production of the moon.

Paradise. The Golden Age. Rain-bow. Water of the sea originally fresh 36

Venus rising from the sea an hieroglyphic emblem of the production of the earth beneath the ocean 47

First great volcanos in the central parts of the earth. From steam, inflammable gas, and vital air. Present volcanos like mole-hills 68

Moon has little or no atmosphere. Its ocean is frozen. Is not yet inhabited, but may be in time 82

Earth's axis changed by the ascent of the moon. Its diurnal motion r.e.t.a.r.ded. One great tide 84

Limestone produced from sh.e.l.ls. Spars with double refractions. Marble.

Chalk 93

Antient statues of Hercules. Antinous. Apollo. Venus. Designs of Roubiliac. Monument of General Wade. Statues of Mrs. Damer 101

Mora.s.ses rest on limestone. Of immense extent 116

Salts from animal and vegetable bodies decompose each other, except marine salt. Salt mines in Poland. Timber does not decay in them. Rock- salt produced by evaporation from sea-water. Fossil sh.e.l.ls in salt mines. Salt in hollow pyramids. In cubes. Sea-water contains about one- thirtieth of salt 119

Nitre, native in Bengal and Italy. Nitrous gas combined with vital air produces red clouds, and the two airs occupy less s.p.a.ce than one of them before, and give out heat. Oxygene and azote produce nitrous acid 143

Iron from decomposed vegetables. Chalybeat springs. Fern-leaves in nodules of iron. Concentric spheres of iron nodules owing to polarity, like iron-filings arranged by a magnet. Great strata of the earth owing to their polarity 183

Hardness of steel for tools. Gave superiority to the European nations.

Welding of steel. Its magnetism. Uses of gold 192

Artificial magnets improved by Savery and Dr. Knight, perfected by Mr.

Michel. How produced. Polarity owing to the earth's rotatory motion. The electric fluid, and the matter of heat, and magnetism gravitate on each other. Magnetism being the lightest is found nearest the axis of the motion. Electricity produces northern lights by its centrifugal motion 193