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The first rule is, to open the mouth sufficiently, and not to mumble or mutter the words.

The second is, to pronounce distinctly every letter and syllable without hurry.

And the third is, to fill the room with the voice, so that the most distant part of the auditory may hear.

417. In regard to gesture, that which is natural is the best, provided it is not awkward and offensive.

The head should be held up, and the speaker should look those he is addressing in the face. His action should be easy, and should keep pace with his voice and the nature of his discourse.

He should also avoid contortions and vulgar grimaces; ease in delivery, being the chief grace of oratory.

XVIII. Of Vegetable Nature.

418. Every substance known to man is divisible into three kingdoms, the Mineral, Vegetable, and Animal. Linnæus thus distinguishes these kingdoms: "Stones grow ;-vegetables grow and live-and animals grow, live, and feel."

Obs. For the Mineral Kingdom, see chapter XX. 419. The existence of all vegetables may be regarded as mechanical, or as similar to that of an animal when asleep, during which time his functions proceed without consciousness. The mechanism of plants is, however, most wonderful; and bespeaks the contrivance of an all-wise and all-powerful Creator.

420. A seed, which is thrown into the earth by the husbandman, is similar in its construction to

the egg of an animal. The earth acts upon it, by means as inexplicable to man, as that by which the sitting of an hen on an egg converts it into a chicken.

421. In a few days, the seed opens, and there issues a green plant, with a number of fibrous threads.

Whatever was the position of the seed, the green sprout struggles through the soil upward into the air; and the fibrous shoots strike downward into the ground; and there imbibe, transmit, or pump up, the moisture, as nourishment to the plant.

422. Nothing is more wonderful than the means of nature for the preservation of seeds; and the contrivances by which they are distributed.

Some seeds are provided with downy wings, as the dandelion, and are impelled by the winds; others are swallowed by animals, and voided again in distant places, being preserved by their coverings, till excited into germination, by the heat of the sun's rays in the following spring.

423. Linnæus divided all plants into 24 classes, and 121 orders; and these into genera, and species, with varieties of the species without number.

Each has its peculiar habitation; and each adapts the nutriment derived from the same earth, so differently, that, by an unknown agency, are produced all the degrees of flavour, odour, poison, and nutriment, which we find in various plants.

Each tree, each plant, from all its branching roots,
Amid the glebe small hollow fibres shoots;
Which drink with thirsty mouths the vital juice,

And to the limbs and leaves their food diffuse;
Peculiar pores peculiar juice receive;

To this, deny, to that, admittance give.-BLACKMORE.

Obs. 1.-Of the different distinctions of leaves only, according to their position and form, above one hundred are enumerated. In all of them, one of the offices, is, to subtilize the abundance of nourishing sap, and to convey it to the little buds. There are two orders of veins and nerves in leaves, one belonging to each surface; and it has been generally observed, that the lower lamina, or under side of the leaf, has the ramifications larger, and is capable of admitting a liquid to pass through them, which those of the upper surface will not. The lower lamina is supposed to be intended for the receiving, preparing, and conveying the moisture imbibed from the rising vapours of the earth, by which trees and plants are greatly nourished; so that one principal use of leaves is to perform, in some measure, the same office for the support of vegetable life, as the lungs of animals do for the subsistence of animal life.

2. Another of the great functions for which the leaves of trees and plants are designed, is that of their foot-stalks nourishing and preparing the buds of the future shoots, which are always formed at the base of these foot-stalks. Leaves, moreover, are designed to shade the buds for future shoots from the sun; which would otherwise exhale and dry up all their moisture. Air evidently passes in at the leaves, and goes through the whole plant, and out again at the roots. If the leaves have no air, the whole plant will die. This has been proved by experiments with the air-pump. And plants not only draw through their leaves some part of their nourishment from the air, but the leaves also perform the necessary work of altering the water received in at the roots into the nature and juices of the plant; and hence it is, that the life of the plant depends so immediately on their leaves.

424. Every plant consists of a root, buds, a trunk or stem, of leaves, of props or arms, of the inflorescence; and of the parts of fructification.

425. In regard to their bulk, plants are divided into trees, shrubs, under-shrubs, and herbs.

According to their respective durations, they are annual, lasting one year, and reproduced from their seed; or biennial, when they are produced in one year and flower the next; perennial, when they last many years.

426. Plants, in regard to the roots, are bulbous, as in onions or tulips; tuberose, as in turnips or potatoes; and fibrous, as in grasses.

They are deciduous, when their leaves fall in autumn; and ever-green, when they are constantly renewed, as in all resinous trees.

They are said to sleep, when they change the appearance of their leaves or flowers at night. They are indigenous, or native; and exotic or foreign.

427. The parts of fructification consist of the calyx, or cup, which is usually the outer green covering of a flower.

The corolla are the delicate leaves or petals of the flower generally coloured, and are the parts which constitute its beauty.

The nectary, or nectarium, is a part in some flowers, supposed to secrete honey, but not easily defined.

428. The calyx and corolla are fine expansions of the outer and inner bark or rind of the plant; and their evident purpose is, to protect certain delicate extensions of the pith and wood, which grow within the corolla, and are called the pistil and the stamen, by the peculiar organization of which the seed is produced.

429. The pistil is provided at its head with a gummy matter, and the stamen with a fine dust

called pollen; and when the dust falls on the head of the pistil, it is there absorbed and carried down the style of the pistil to the germen or seed-vessel in the centre of the flower; where the seed is, in consequence, produced within a pericarp, afterwards called fruit.

430. Fruits, which afford us so many luxuries, are, in fact, nothing more than the covering, which protects the seed of plants, and called by botanists Pericarps.

Some pericarps are pulpy, as apples, pears, nectarines, &c.; some are hard, as nuts: and some scaly, as the cones of fir-trees

Your contemplation further yet, pursue;
The wondrous world of vegetables view!
See various trees, their various fruits, produce,
Some for delightful taste, and some for use.
See sprouting plants enrich the plain and wood,
For physic some, and some designed for food.
See fragrant flowers, with different colours dy'd,
On smiling meads unfold their gaudy pride.

BLACKMORE.

431. It must not then be forgotten, that the design of the beautiful flowers which cover the earth is to create the seed of future trees; that the leaves or corolla of the flowers are merely protections of the delicate pistil, stamen, and germen; that in this last are produced the seeds; and that for their protection is provided the pericarp, which we call the fruit.

Go, mark the matchless workings of the Power,
That shuts within the seed the future flower;
Bids these, in elegance of form excel,
In colour these, and those delight the smell;
Sends Nature forth, the daughter of the Skies,
To dance on earth, and charm all human eyes.

COWPER.

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