Method of Drying and Preserving PLANTS for Botanists

Method of Drying and Preserving PLANTS for Botanists.—Many methods have been devised for the preservation of plants: we shall relate only those that have been found most successful.

Wabering's botanical arrangement, introd. p. 48.
First prepare a press, which a workman will make by the following directions. Take two planks of a wood not liable to warp. The planks must be two inches thick, 18 inches long, and 12 inches broad. Get four male and four female screws, such as are commonly used for securing sash-windows. Let the four female screws be let into the four corners of one of the planks, and corresponding holes made through the four corners of the other plank for the male screws to pass through, so as to allow the two planks to be screwed tightly together. It will not be amiss to face the bearing of the male screws upon the wood with iron plates; and if the iron plates went across from corner to corner of the wood, it would be a good security against the warping.

Secondly, get half a dozen quires of large soft spongy paper (such as the stationers call blossom blotting paper is the best), and a few sheets of strong pasteboard. The plants you wish to preserve should be gathered in a dry day, after the sun hath exhaled the dew; taking particular care to collect them in that state wherein their generic and specific characters are most conspicuous. Carry them home in a tin-box nine inches long, four inches and a half wide, and one inch and a half deep. Get the box made of the thinnest tinned iron that can be procured; and let the lid open upon hinges. If any thing happens to prevent the immediate use of the specimens you have collected, they will be kept fresh two or three days in this box much better than by putting them in water. When you are going to preserve them, suffer them to lie upon a table until they become limber; and then they should be laid upon a pasteboard, as much as possible in their natural form, but at the same time with a particular view to their generic and specific characters. For this purpose it will be advisable to separate one of the flowers, and to display the generic character. If the specific character depends upon the flower or upon the root, a particular display of that will be likewise necessary. When the plant is thus disposed upon the pasteboard, cover it with eight or ten layers of spongy paper, and put it into the press. Exert only a small degree of pressure for the first two or three days; then examine it, unfold any unnatural plaits, rectify any mistakes, and, after putting fresh paper over it, screw the press harder. In about three days more separate the plant from the pasteboard,

if it is sufficiently firm to allow of a change of place; put it upon a fresh pasteboard, and, covering it with fresh blossom-paper, let it remain in the press a few days longer. The press should stand in the sun-shine, or within the influence of a fire.

When it is perfectly dry, the usual method is to fasten it down, with paste or gum-water, on the right-hand inner page of a sheet of large strong writing-paper. It requires some dexterity to glue the plant neatly down, so that none of the gum or paste may appear to defile the paper. Press it gently again for a day or two, with a half sheet of blossom-paper betwixt the folds of the writing-paper. When it is quite dry, write upon the left-hand inner page of the paper the name of the plant; the specific character; the place where, and the time when, it was found; and any other remarks you may think proper. Upon the back of the same page, near the fold of the paper, write the name of the plant, and then place it in your cabinet. A small quantity of finely powdered arsenic, or corrosive sublimate, is usually mixed with the paste or gum-water, to prevent the devastations of insects; but the seeds of havens-acre finely powdered will answer the same purpose, without being liable to corrode or to change the colour of the more delicate plants. Some people put the dried plants into the sheets of writing paper, without fastening them down at all; and others only fasten them by means of small slips of paper, pasted across the stem or branches. Where the species of any genus are numerous, and the specimens are small, several of them may be put into one sheet of paper.

Another more expeditious method is to take the plants out of the press after the first or second day; let them remain upon the pasteboard; cover them with five or six leaves of blossom paper, and iron them with a hot smoothing iron until they are perfectly dry. If the iron is too hot, it will change the colours; but some people, taught by long practice, will succeed very happily. This is quite the best method to treat the orchis and other slimy mucilaginous plants.

Another method is to take the plants when fresh gathered, and, instead of putting them into the press, immediately to fasten them down to the paper with strong gum water: then dip a camel-hair pencil into spirit-varnish, and varnish the whole surface of the plant two or three times over. This method succeeds very well with plants that are readily laid flat, and it preserves their colours better than any other. The spirit-varnish is made thus. To a quart of highly rectified spirit of wine put five ounces of gum sandarach; two ounces of mastic in drops; one ounce of pale gum elemi, and one ounce of oil of spike-lavender. Let it stand in a warm place, and shake it frequently to expedite the solution of the gums.

Where no better convenience can be had, the specimens may be disposed systematically in a large folio-book; but a vegetable cabinet is upon all accounts more eligible. In Plate CCCXVII. there is a section of a cabinet, in the true proportions it ought to be made, for containing a complete collection of British plants. By the assistance of this drawing, and the adjoining scale, a workman will readily make one. The drawers must have backs and sides, but no other front than a small.

Plants. small ledge. Each drawer will be 14 inches wide, and 10 inches from the back to the front, after allowing half an inch for the thickness of the two sides, and a quarter of an inch for the thickness of the back. The sides of the drawers, in the part next the front, must be sloped off in a serpentine line, something like what the workmen call an ogee. The bottoms of the drawers must be made to slide in grooves cut in the uprights, so that no space may be lost betwixt drawer and drawer. After allowing a quarter of an inch for the thickness of the bottom of each drawer, the clear perpendicular space in each must be as in the following table.

This cabinet shuts up with two doors in front; and the whole may stand upon a base, containing a few drawers for the reception of duplicates and papers.

Fossil Plants. Many species of tender and herbaceous plants are found at this day, in great abundance, buried at considerable depths in the earth, and converted, as it were, into the nature of the matter they lie among; fossil wood is often found very little altered, and often impregnated with substances of almost all the different fossil kinds, and lodged in all the several strata, sometimes firmly imbedded in hard matter; sometimes loose: but this is by no means the case with the tenderer and more delicate subjects of the vegetable world. These are usually immersed either in a blackish flaty substance, found lying over the strata of coal, else in loose nodules of ferruginous matter of a pebble-like form, and they are always altered into the nature of the substance they lie among: what we meet with of these are principally of the fern kind; and what is very singular, though a very certain truth, is, that these are principally the ferns of American growth, not those of our own climate. The most frequent fossil plants are the polypody, spleenwort, osmund, trichomanes, and the several larger and smaller ferns; but besides these there are also found pieces of the equisetum or horse-tail, and joints of the stellated plants, as the clivers, madder, and the like; and these have been too often mistaken for flowers; sometimes there are also found complete grasses, or parts of them, as alders, reeds, and other watery plants; sometimes the ears of corn, and not unfrequently the twigs or bark, and impressions of the bark, and fruit of the pine or fir kind, which have been, from their scaly appearance, mistaken for the skins of fishes; and sometimes, but that very rarely, we meet with mosses and sea-plants.

Many of the ferns not unfrequently found, are of

very singular kinds, and some species yet unknown to us; and the leaves of some appear set at regular distances, with round protuberances and cavities. The stones which contain these plants split readily, and are often found to contain, on one side, the impression of the plant, and on the other the prominent plant itself; and, beside all that have been mentioned, there have been frequently supposed to have been found with us ears of common wheat, and of the maize or Indian corn; the first being in reality no other than the common endmost branches of the fire, and the other the thicker boughs of various species of that and of the pine kind, with their leaves fallen off; such branches in such a state cannot but afford many irregular tubercles and papillae, and, in some species, such as are more regularly disposed.

These are the kinds most obvious in England; and these are either immersed in the flaty stone which constitutes whole strata, or in flattened nodules, usually of about three inches broad, which readily split into two pieces on being struck.

They are most common in Kent, on coal-pits near Newcastle, and the forest of Dean in Gloucestershire; but are more or less found about almost all our coal-pits, and many of our iron mines. Though these seem the only species of plants found with us, yet in Germany there are many others, and those found in different substances. A whitish stone, a little harder than chalk, frequently contains them: they are found also often in a grey flaty stone of a firmer texture, not unfrequently in a blackish one, and at times in many others. Nor are the bodies themselves less various here than the matter in which they are contained: the leaves of trees are found in great abundance, among which those of the willow, poplar, whithorn, and pear trees, are the most common; small branches of box, leaves of the olive-tree, and stalks of garden thyme, are also found there; and sometimes ears of the various species of corn, and the larger as well as the smaller mosses in great abundance.

These seem the tender vegetables, or herbaceous plants, certainly found thus immersed in hard stone, and buried at great depths in the earth: others of many kinds there are also named by authors; but as in bodies so imperfect errors are easily fallen into, these seem all that can be ascertained beyond mere conjecture.

Plants, method of preserving them in their original shape and colour. Wash a sufficient quantity of fine sand, so as perfectly to separate it from all other substances; dry it; pass it through a sieve to clear it from any gross particles which would not rise in the washing: take an earthen vessel of a proper size and form, for every plant and flower which you intend to preserve; gather your plants and flowers when they are in a state of perfection, and in dry weather, and always with a convenient portion of the stalk: heat a little of the dry sand prepared as above, and lay it in the bottom of the vessel, so as equally to cover it; lay the plant or flower upon it, so as that no part of it may touch the sides of the vessel: first or shake in more of the same sand by little upon it, so that the leaves may be extended by degrees, and without injury, till the plant or flower is covered about two inches thick: put the vessel into a stove, or hot-house, heated by little and little to the 50th degree; let it stand

Plant stand there a day or two, or perhaps more, according to the thickness and succulence of the flower or plant; then gently shake the sand out upon a sheet of paper, and take out the plant, which you will find in all its beauty, the shape as elegant, and the colour as vivid as when it grew.

Some flowers require certain little operations to preserve the adherence of their petals, particularly the tulip; with respect to which it is necessary, before it is buried in the sand, to cut the triangular fruit which rises in the middle of the flower; for the petals will then remain more firmly attached to the stalk.

A hirtus ficcus prepared in this manner would be one of the most beautiful and useful curiosities that can be.

Moving PLANT. See HEDYSARUM.

Sea PLANT. See SEA PLANT.

Sensitive PLANT. See MIMOSA and SENSITIVE PLANT.