PLANTS growing on Animals. See INSECTS giving root to Plants.
Sexes of PLANTS. See SEXES and BOTANY.
Colours of PLANTS. See COLOUR of Plants.
Colours extracted from PLANTS. See COLOUR-making.
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.
First prepare a press, which a workman will make by the following directions. Take two planks of 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 blofom 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 where-in 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 happen 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 depend 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 plats, rectify any mistakes, and, after putting fresh paper over it, press 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 blofom paper, let it remain in the press a few days longer. The press should stand in the sunshine, 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 blofom-paper between 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 degradations of insects; but the seeds of flaxes-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 blofom paper, and iron them with a hot smoothing
(c) In the 2d volume of Transactions of the Linnean Society, we find Dr Percival's reasoning very ably combated, as far as he draws his consequences from the external motions of plants; where it is argued, that these motions, though in some respects similar to those of animals, can and ought to be explained, without concluding that they are endowed either with perception or volition. Mr Townson concludes his paper in these words: "When all is considered (says he), I think we shall place this opinion among the many ingenious flights of the imagination, and soberly follow that blind impulse which leads us naturally to give sensation and perceptivity to animal life, and to deny it to vegetables; and so still say with Aristotle, and our great master Linnaeus, Vegetabilia crescunt & vivunt; animalia crescunt, vivunt, & sentiunt." smoothing iron until they are perfectly dry. If the iron be 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. With the affluence of the following description a workman may readily make one. The drawers must have backs and sides, but no other front than a 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 twofolds, 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:
| I. Two-tenths of an inch. | XIV. Three inches and eight-tenths. | |---------------------------|-------------------------------------| | II. One inch and two-tenths. | XV. Three inches and four-tenths. | | III. Four inch and six-tenths. | XVI. One inch and three-tenths. | | IV. Ten inches and three-tenths. | XVII. Two inches and eight-tenths. | | V. Seven inches and eight-tenths. | XVIII. Six-tenths of an inch. | | VI. Two inches and two-tenths. | XIX. Ten inches. | | VII. Two-tenths of an inch. | XX. One inch and nine-tenths. | | VIII. One inch and four-tenths. | XXI. Four inches and four-tenths. | | IX. Two-tenths of an inch. | XXII. Two inches and five-tenths. | | X. Two inches and eight-tenths. | XXIII. One inch and two-tenths. | | XI. One inch and two-tenths. | XXIV. Seventeen inches. | | XII. Three inches and five-tenths. | |
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, ophiodon, 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 griffins, or parts of them, as also 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 for times, 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 firs, 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 flatted nodules usually of about three inches broad, which readily split into two pieces on being struck.
They are most common in Kent, in 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 gray 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, white thorn, 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