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the name of flower to these envelopes, which are often remarkable for the brilliancy of their colours, the elegance of their forms and the fragrance of their perfumes.

Method of preserving Plants, and of preparing an Herbarium.

Plants collected for analysis, may be preserved fresh many days, in a close tin box, by occasionally sprinkling them with water; they may also be preserved by placing their stems in water, but not as well by the latter, as the former method. While attending to the science of Botany, you should keep specimens of all the plants you can procure. An herbarium neatly arranged is beautiful, and may be rendered highly useful, by affording an opportunity to compare many species together, and it likewise serves to fix in the mind the characters of plants. It is a good method in collecting plants for an herbarium, to have a port-folio, or a book in which they may be placed before the parts begin to wilt. Specimens should be placed between the leaves of paper, either newspaper or any other kind which is of a loose texture, and will easily absorb the moisture of the plants; a board with a weight upon it should then be placed upon the paper containing them; the plants should be taken out frequently at first; as often as once or twice a day, and the paper dried, or the plants placed between other dry sheets of paper. Small plants may be dried between the leaves of a book. Plants differ in the length of time required for drying as they are more or less juicy; some dry in a few days, others not sooner than two or three weeks. When the specimens are dry, and a sufficient number collected to commence an herbarium, a book should be procured, composed of blank paper, (white paper gives the plants a more showy appearance.) A quarto size is more convenient than a folio. Upon the first page of each leaf should be fastened one or more of the dried specimens, either with glue or by means of cutting through the paper, and raising up loops under which the stems may be placed. By the sides of the plants should be written the class, order, generic, and specific name; also the place where found, and the season of the year. The colours of

plants frequently change in drying; the blue, pale red, and white, often turn black, or lose their colour; yellow, scarlet, violet, and green, are more durable. An herbarium should be carefully guarded against moisture and insects; as a security against the latter, the plants may be brushed over with corrosive-sublimate.

Botanical Excursions.

As a healthful and agreeable exercise, we would recommend frequent botanical excursions; you will experience more pleasure from the science, by seeing the flowers in their own homes; a dry grove of woods, the borders of little streams, the meadows, the pastures, and even the waysides, will afford you constant subjects for botanical observations. To the hardier sex, who can climb mountains, and penetrate marshes, many strange and interesting plants will present themselves, which cannot be found except in their peculiar situations; of these you must be content to obtain specimens, without seeing them in their native wilds. You will, no doubt, easily obtain such specimens, for there is, usually, among the cultivators of natural science, a generosity in affording assistance, and imparting to others the treasures which nature lavishes upon those who have a taste to enjoy them.

Method of preserving plants, and of preparing an herbarium-Botanical excursions.

Poisonous Plants, and those which are not Poisonous.

In collecting flowers, you should be cautious with respect to poisonous plants. Such as have five stamens and one pistil, with a corolla of a dull, lurid colour, and a disagreeable smell, are usually poisonous; the Thorn apple (stramonium) and the Tobacco are examples. The Umbelliferous plants, which grow in wet places, have usually a nauseous smell: such plants are poisonous, as the water hemlock. Umbelliferous plants which grow in dry places, usually have an aromatic smell, and are not poisonous, as Caraway and Fennel.

Plants with Labiate corollas, and containing their seeds in capsules, are often poisonous, as the Foxglove; (Digitalis ;) also, such as contain a milky juice, unless they are compound flowers. Such plants as have horned or hooded nectaries, as the Columbine and Monk's-hood, are mostly poisonous.

Among plants which are seldom poisonous, are the compound flowers, as the Dandelion and Boneset; such as have labiate corollas, with seeds lying naked in the calyx, are seldom or never poisonous; the Mint and Thyme are examples of such plants. The Papilionaceous flowers, as the pea and bean; the Cruciform, as the radish and mustard, are seldom found to be poisonous. Such plants as have their stamens standing on the calyx, as the rose and apple, are never poisonous; neither the grass-like plants with glume calyxes, as Wheat, Rye, and Orchard-grass, (Dactylis.)

Proper Flowers for Analysis.

In selecting flowers for analysis, you must never take double ones; the stamens (and in many cases the pistils also) change to petals by cultivation, therefore you cannot know by a double flower, how many stamens or pistils belong to it in its natural state. Botanists seem to view as a kind of sacrilege, the changes made by culture, in the natural characters of plants; they call double flowers, and variegated ones, produced by a mixture of different species, monsters and deformities. These are harsh expressions to be applied to Roses and Carnations, which our taste must lead us to admire, as intrinsically beautiful, although their relative beauty, as subservient to scientific illustration, is certainly destroyed by the labour of the florist. The love of native wild flowers is no doubt greatly heightened by the habit of seeking them out, and observing them in their peculiar situations. A Botanist, at the discovery of some lowly plant, growing by the side of a brook, or almost concealed in the cleft of a rock, will often experience more vivid delight than could be produced by a view of the most splendid exotic. Botanical pursuits render us interested in every vegetable production: even such as we before looked upon as useless, present attractions as objects of scientific investigation, and become associated with the pleasing recollections, arising from the gratification of our love of knowledge. A peculiar interest is given to conversation by an acquaintance with any of the natural sciences; and when females shall have more generally obtained access to these delightful sources of pure enjoyment, we may hope that scandal, which oftener proceeds from a want of better subjects, than from malevolence of disposition, shall cease to be regarded as a characteristic of the sex. It is important to the cause of science, that it should become fashionable; and as one means of effecting this, the

Poisonous plants-Compound flowers seldom poisonous -Double flowers not proper for analysis-Effect of Botanical pursuits-Of an acquaintance with any of the natural sciences.

parlours of those ladies, who have advantages for intellectual improvement, should more frequently exhibit specimens of their own scientific taste. The fashionable et ceteras of scrap books, engravings, and albums, do not reflect upon their possessors any great degree of credit. To paste pictures, or pieces of prose or poetry, into a book; or to collect in an album the wit and good sense of others, are not proofs of one's own acquirements; and the possession of elegant and curious engravings, indicates a full purse, rather than a well stored mind; but herbariums and books of impressions of plants,* drawings, &c. show the taste and knowledge of those who execute them.

It is unfortunately too much the case, that female ingenuity, (especially in the case of young ladies after leaving school,) is in a great degree directed to trivial objects, which have no reference either to utility, or to moral and intellectual improvement. But a taste for scientific pursuits once acquired, a lady will feel that she has no time for engagements, which neither tend to the good of others, nor to make herself wiser or better.

* Manner of taking impressions of leaves.-Hold oiled paper over the smoke of a lamp until it becomes darkened; to this paper, apply the leaf, having previously warmed it between the hands, that it may be pliant. Place the lower surface of the leaf upon the blackened paper, that the numerous veins which run through its extent, and which are so prominent on this side, may receive from the paper a portion of the smoke. Press the leaf upon the paper, by placing upon it some thin paper, and rubbing the fingers gently over it, so that every part of the leaf may come in contact with the sooted oil-paper. Then remove the leaf, and place the sooted side upon clean white paper, pressing it gently as before; upon removing the leaf, the paper will present a delicate and perfect outline, together with an accurate exhibition of the veins which extend in every direction through it, more correct and beautiful than the finest drawing.

Female ingenuity too often directed to trivial objects.

PART II.

LECTURE VI.

IMPORTANCE OF OBSERVING EXTERNAL OBJECTS-VEGETABLES CONSIST OF TWO SETS OF ORGANS-OF THE ROOT.

THE exercises which constitute the principal part of our previous course of lectures, are chiefly designed to assist you in practical botany. It is not expected that you are to be the passive receivers of instruction, but that you are to compare with real objects, the descriptions which are presented; by doing this faithfully, you will find your minds gradually strengthened, and more competent to compare and judge in abstract studies, where the subjects of investigation are in the mind only, and cannot, like the plants, be looked at with the eyes, and handled with the hands.

All our thoughts, by means of the senses, are originally derived from external objects. Suppose an infant to exist, who could neither hear, see, taste, smell, nor feel; all the embryos of thought and emotion might exist within it; it might have a soul capable of as high attainments as are within the reach of any created beings; but this soul, while thus imprisoned, could gather no ideas; the beauty of reflected light, constituting all the variety of colouring; the harmony of sounds, the fragrant odours of flowers, the various flavours, which are derived from our sense of taste, the ideas of soft, smooth, or hard; all must for ever remain unknown to the soul confined to a body having no means of communication with the world around it. The soul, in its relation to external objects, may be compared to the embryo plant, which, imprisoned within the seed, would for ever remain inert, were no means provided for its escape from this confinement, and no communication opened between it and the air, the light, and vivifying influence of the earth.

Since our first ideas are derived from external nature, is it not a rational conclusion that we should add to this original stock of knowledge, by a continued observation of objects addressed to our senses? After the years of infancy are past, and we begin to study books, should we, neglecting sensible objects, seek only to gain ideas from the learned; or, in other words, should we, in the pursuit of human sciences, overlook the works of God?

Having now enabled you to understand the method of analyzing plants, we shall proceed to consider more fully the different organs of plants, with the uses of each, in the vegetable economy.

In plants, as well as animals, each part or organ is intimately connected with the whole; and the vegetable, as well as the animal being, depends for its existence on certain laws of organization.

We shall consider the vegetable organs under two classes; the first, including such organs as promote the growth of the plant, as the root, leaves, &c.; the second, such as perfect the seed, and thus provide for the reproduction of the species, called organs of fructification.

Study of external objects strengthens the mind-Abstract studies facilitated by acquaintance with the natural sciences-Our first ideas gained by the senses-Analogy between the soul and the embryo plant-We should not confine our attention exclusively to books-Vegetable, as well as animal existence, depends on certain laws of organization-Two kinds of organs of vegetables.

Of the Root.

The root (radix) is that part of the vegetable which enters the earth, and extends in a direction contrary to the growth of the stem ; it supports the plant in an upright position, and at the same time gives nourishment to every part of it. There are exceptions to the general fact, of a root being fixed in the ground; some plants, as the pond-lily, grow in water, and are called aquatic, (from aqua, water,) some, like the mistletoe, have no root, but fix themselves upon other plants, and derive sustenance from them; such are called parasites.*

The Root consists of two parts, the Caudex, or main body of the Root, and the Radicle, or fibres; these are capillary tubes, which absorb the nourishment that is conveyed to other parts of the plant. This nourishment ascending through the stem, experiences in the leaves and green parts of the plant, an important change, effected, in part, through the agency of air and light; and a portion of it, through a different set of vessels, flows back, in what is called the returning sap, or cambium.

Between the Caudex and stem is a point, called the neck, or root stock; any injury to this part is followed by the death of the plant. Duration of Roots.

Roots, with respect to duration, are annual, biennial, or perennial. Annual Roots-are such as live but one year. They come from the seed in the spring, and die in autumn, including such as are raised from the seed every year; as peas, beans, cucumbers, &c.

Biennial Roots-are such as live two years. They do not produce any flowers the first season, the next summer they blossom, the seeds mature, and the roots die. The roots of cabbages are often, after the first season, preserved in cellars during the winter. In the spring they are set out in gardens, and produce flowers; the petals of which, in time, fall off, and the germ grows into a pod which contains the seed. The root having performed this office, then dies, and no process can restore it to life; the flowering is thought to exhaust the vital energy or living principle. The onion, beet, and carrot, are biennial plants.

Perennial Roots-are those whose existence is prolonged a number of years to an indefinite period; as the asparagus, geranium, and rose; also trees and shrubs. Climate and cultivation affect the duration of the roots of vegetables. Many perennial plants become annual by transplanting them into cold climates: the garden nasturtion, originally a perennial shrub in South America, has become in our latitude an annual plant.

Forms of Roots.

There are many varieties in the forms of roots; the most important are the branching, fibrous, spindle, creeping, granulated, tuberous, and bulbous.

1st. Branching root, (Fig. 12.) This is the most common kind; it consists of numerous ramifications, resembling in appearance the

*The word parasite, from the Greek para, with, and sitos, corn, was first applied to those who had the care of the corn used in religious ceremonies, and were allowed a share of the sacrifice; afterward it was applied to those who depended on the great, and earned their welcome by flattery; by analogy, the term is now applied to plants which live upon others.

Definition of the root-Aquatic roots-Parasites-Division of the root-Annual roots -Biennial-Perennial roots-Classification of roots as founded upon their formsBranching root.

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