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what inclining to Purple. The Garnet is fomewhat like it, and perhaps of the fame Species. The Hyacinth is fometimes of a deep red, and fometimes of a yellow Colour. The Amethyft is of a bright Purple. The Emerald, a Grafs Green. The Beryl, a Sea or bluish Green. The Sapphire a Sky Blue. The Topaz or Chryfolite is of a gold Colour. These are all tranfparent. Of Opake Stones, or fuch as are only half tranfparent, the Cornelian is beft; it is of a pale red, fometimes bordering upon Orange. The Onyx is of a greyish Caft. The Turquoife is betwixt blue and green. Lapis Lazuli is studded with Spots of Gold on an azure Ground. But all thefe, with many others, might perhaps be ranked under the Claffes of Agate and Jafper: Only the Agate is a little more transparent, harder, and will take a finer Polish; but both the Agate and Jasper vary their Colours extremely.

of the Magnet

or Loudftone.

This wonderful Stone is ufually found in Iron Mines, and is produc'd in moft Countries of the World, China, Bengal, Arabia, Hungary, Germany, and England. It is a heavy Stone, fomething refembling the Ore of Iron, only clofer and more ponderous. It is endowed with fome furprizing Qualities and Powers. It attracts Iron, which will adhere to it very ftrongly; which Virtue it alfo communicates to the Iron fo attracted. In every Magnet there are two Poles, one of which points Northwards, the other Southwards; and if the Magnet be divided into ever fo many Pieces, the two Poles will be found in each Piece. It is this Property which has rendered it so useful in improving the Art of Navigation, for by the Help of a Needle properly touch'd on the Loadftone, the Sailor directs the Courfe of his Ship to whatever Quarter of the World he pleases, the Property of pointing towards the North being communicated from the Stone to the Needle. But to give you a perfect Notion of this, it would be neceffary to defcribe and explain to you the Mariner's Compafs, which as it would lead me fomewhat out of the way, I fhall at prefent decline. Thus you fee the Bowels of the Earth may be confidered as a Storehouse, containing a Number of Things for the Ufe of Man; many of which it would have been very inconvenient to have put any where elfe: Here they are out of his Way, yet ready at his Hand. But we will now afcend to the Surface of the Earth, and view the Wonders of the Vegetable World.

CHAP.

W

CHA P. III.

Of Trees, Plants, Herbs, and Flowers.

HAT a delightful Verdure cloaths the Surface of this earthly Globe! How charming to the Senfe, how agreeable to the Imagination are its various Profpects! Hills crown'd with Woods, and Vallies rich with Herbage; Fields waving with golden Crops of various Kinds of Grain, and Meadows enamell'd with a thousand Herbs and Flowers. How beautiful are their Colours! How rich, how fragrant, how refreshing the Odours which they breathe! How wonderful and furprizing to Reafon are the Formation and Structure of their Parts! How useful and beneficial to the Life of Man their medicinal Virtues! Manifold are the Works of God, in Wifdam has he made them all! The common Principle which animates this Part of his Works is Vegetation. I will firft endeavour to give you fome fmall Knowledge of that, and then proceed to confider a few of the Properties and Virtues of the particular Species. Every thing that grows upon the Face of the Earth, whether Tree, or Plant, or Herb, or Flower, is called a Vegetable; has Parts and Organs form'd for Generation and Growth, though not Senfation; and contains a kind of living Principle called Vegetation; the Bufinefs of which Principle is to concoct the indigefted Earth, and Salts, and Water which afcend through the Roots, and to affimilate them to the Nature of the Plant. Hence, though growing on the fame Bed of Earth, and nourished with the fame Sun and Air and Water, yet one fhall carry an oily, another a milky Juice in its Veins; one fhall be of a yellow Colour, another of a red, and a third of a green, fhall yield an agreeable, another an offenfive Smell; one is sweet to the Taffe, another bitter, another four; one is nourishing, another is poisonous; one laxative, another aftringent. It is generally thought among Naturalifts, that Water is the principal Food of Vegetation, and perhaps it is; yet a due Mixture of Earth and Air is very neceflary to the Health and Vigour of all Vegetables whatfoever. Some indeed require a greater Proportion of Earth, and fome of Water, than others do. But pure Water unimpregnated with any terreftrial Matter, if fuch a Thing could be had, would nourish no Plant at all, neither on the contrary would dry Sand. Boerhaave defines a Vegetable to be a Body generated of the Earth, to

one

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which it adheres, or is connected by Parts called Roots, thro' which it receives the Matter of its Nourishment and Increase; and confifts of Juices and Veffels fenfibly distinct from each other. The Procefs of Nature in Vegetation is as follows. The Seed being committed to the Earth, and received into her Bofom, the warm Vapours thereof, joined with the Heat of the Sun, perform the Office of Incubation, difpofing the Seed to receive the vivifying Power. Now the Earth every where abounds with Veins and Channels, wherein the Dew and RainWater, impregnated with fertile Salts, glide like the Chyle and Blood in the Veins and Arteries of Animals; and this Moisture meeting with a newly-depofited Seed, is ftrained through the Pores of the outer Rind, on the Infide whereof lie one or two thick feminal Leaves, which confist of a great Number of little Veffels or Bladders, with a Tube, correfpondent to the Navel String in Animals; the Moisture of the Earth, I fay, thus ftrained through the Rind of the Sced, makes a flight Fermentation with the proper Juices contained in it, which fermented Liquor is conveyed, by the aforefaid umbilical Tube, to the Trunk of the little Plant, from thence to the Germ or Bud which is contiguous to it, upon which fucceeds a Vegetation and Increase of the Parts. This, according to the beft Naturalifts, is the Procedure of Nature in the Vegetation of Plants. But the Writers on this Subject, fuch as Malpighi, Boerhaave, Hales, Miller, and fome others, will inform you farther, whenever you are difpofed to confult them. I will now, according to my Promife, give you the Natural Hiftory of five or fix of the most remarkable Vegetables, and then proceed to the Confideration of Animal Life.

Qak.

The OAK is one of the largest and most useful of all Vegetables. It is the ftrongest and most of the durable of all Timber; and will continue firm and found either in Air or Water longer than any other Wood. Hence the great Value of it to Ship-builders, Carpenters, and other Architects. It is produced from the Acorn, a fmall Fruit which it bears, very useful in feeding Hogs, &c. and is faid by Naturalifts to grow three hundred Years.

Vine.

The VINE is a Plant or Shrub of the reptile Kind, fupporting itself by creeping or climbing of the up any thing which ftands near it. It is famous for its Fruit called Grapes, which it produces in Bunches, and from the Juice of which is made that dangerous

Liquor,

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