by the abundance of their juice, are enabled both to allay the sensation of present heat and thirst, and to repair the loss of that natural moisture of the body, which is continually passing from it in the form of either sensible or insensible perspiration. Even in the temperate climate of our own island, how many days are there, during the summer, in which such fruits are most refreshing: and to gratify the desire of that refreshment we import such species as are capable of bearing a long voyage; among which the orange is a very principal article of import: nor would it be easy to calculate the myriads of that fruit which are annually consumed in this country. But the cognate fruit, the lemon, at the same time that, on account of the grateful and aromatic flavour of its juice, it is occasionally as eagerly sought as the orange, serves a still higher purpose: for the acid contained in it has been successfully employed, as an antidote and a remedy for one of the most dreadful diseases to which mariners are subject. Sea-scurvy in fact has all but disappeared since the general adoption of this remedy*. SECTION IV. Vegetables as applicable to Medicine. Ir vegetables are valuable on account of their power of affording sustenance and keeping the body in a state of health, they are also valuable on account of their power of restoring health where it has been impaired for, however sceptical some minds may be as to the powers of medicine in general, and however ignorant even the most sagacious and experienced medicinal practitioners may be as to the precise mode in which any medical substance acts on the human constitution; yet this at least is certain, that, in by far the greater number of instances, certain symptoms which indicate a disturbed state of the system are mitigated, and finally subdued, in consequence of the exhibition, to use a technical term, of certain reputed remedies. And it is open to the observation of almost every one, that the vegetable kingdom is the most fertile source, not only of the commonest and least efficient, but of some of the most powerful medicines with which we are acquainted. Nor can we doubt, when we see similar effects resulting from the use of the same medicines in figs in order to make a nest for their eggs; and the wound they inflict accelerates the ripening of the fruit nearly three weeks; thus leaving time for the second crop to come to maturity in due season." (Vol. ii. p. 41, 42.) It is probable that fresh vegetables of any kind are sufficient to prevent or to remove scurvy: for it is stated in Sauer's account of Billings's expedition, that that disease disappeared, even in so high a northern latitude as the Aleutan islands, as soon as the new vegetation sprang up in April (p. 276); and many other evidences of the same fact might be easily adduced. individuals of very different constitutions, that the peculiar qualities of those substances, with respect to the effects they produce in the human system, were imparted to them by nature with a view to their application to those ends. It may have happened to any one in the course of the last few years, during which intermittent fever or ague has prevailed very generally in this country, to witness the severe nature of some symptoms of that disease; paroxysms of dreadful rigour or shivering; nausea; intense headache, with delirium; paralytic affections of the limbs; and burning heat of the whole body, terminating in profuse perspiration: and whoever has witnessed such symptoms, recurring in the same individual at stated intervals, has probably seen their return at once arrested by a few doses of Peruvian bark, in the state of powder; the effect of which remedy, in subduing a violent disease, compared with the small quantity of it employed for that purpose, has been not inelegantly though playfully illustrated by that passage of the Georgics, in which the husbandman is taught to allay the occasional contests and agitations of the bees, by scattering a handful of dust among them. "Hi motus atque hæc certamina tanta And, if the vegetable kingdom had failed to afford any other medicinal substance than this, mankind would have still had ample cause for thankfulness. But, even in the instances of those remedies from which nothing beyond a present or temporary alleviation is expected, the benefit usually accruing cannot easily be estimated at too high a rate: and one remedy there is, of this nature, for which mankind is indebted to the vegetable kingdom exclusively. How often has not opium lulled the most excruciating agonies of pain? how often has it not restored the balm of sleep to the almost exhausted body; or quieted those nervous agitations of the whole system, the terrors of which none perhaps can duly appreciate but those who have experienced them? There are however diseased or unnatural states of the body, in which no direct remedy can be applied, and all soothing means would not only be ineffectual, but fatal: in such states those substances, which are directly opposed in quality to opium, and irritate instead of soothing the surfaces to which they are applied, are valuable precisely on that account: they rouse the system, for instance, from a state of lethargy, which otherwise would probably terminate in death; or they stimulate the stomach to reject any substance of a poisonous nature, which may have been either intentionally or accidentally introduced into it, and they thus contribute to the preservation of life. Remedies of this character, though not exclusively belonging to the vegetable kingdom, are frequently afforded by it. But, in enumerating the medicinal auxiliaries which mankind derive from the vegetable kingdom, let me not omit the restorative virtue of that gift of Heaven, which, though by its abuse it may intoxicate the mental faculties and undermine the general health of the body, is calculated most assuredly, when rightly used, not only to revive the drooping energies, but to rekindle the almost expiring spark of life. Survey the wretched subject of what is called typhus, while oppressed by those symptoms which justify the use of this restorative; when the glazed eye and squalid skin, the feeble circulation and muttering delirium, announce the near approach of death, unless the proper medicine be interposed; and then watch the bene ficial effect of this divine remedy. They who have witnessed the progress of typhus fever in some of its forms, and in individuals who have lived in crowded and ill-ventilated habitations, will acknowledge that in very many instances wine alone has, humanly speaking, rescued the patient from the grave. Nor will it be irrelevant to the general subject of this treatise to consider the natural origin of wine: by which I mean, not the mode or time of its discovery; either of which it would be as useless as vain to attempt to investigate, since this liquid was in common use at a period long antecedent to history: but by its natural origin I mean the circumstances under which it is usually produced. There is a law in nature, by which organised bodies, vegetables as well as animals, are disposed to undergo spontaneous decomposition very soon after they have ceased to live; the ultimate result of which is, a resolution into their elementary principles; in other words, they pu trefy and perish. But even in this state, in which they are deprived of all their former properties, they administer to the good of man; and, under the name of manure, are known as the principal means of fertilizing the ground; from whence all his food is ultimately obtained. The circumstances, however, which accompany this change in vegetables, differ very much from those which attend the corresponding change in animals; and may be well illustrated by a reference to the process of making any common wine. If a sufficient quantity of the juice of ripe grapes, or of any other saccharine fluid, be exposed to a moderately warm temperature, an internal movement of its particles soon begins to take place; which is technically called fermentation: and during the period when this is going on, the sugar of the liquor is, in part, converted into wine. If the fermentation be now arrested by the proper means, the whole mass of the liquid may be preserved in nearly the same state for a longer or shorter period, in proportion to the quantity of wine contained in it but if, after the vinous fermentation, as it is called, has been completed, the temperature be to a certain degree increased, the wine is converted into vinegar by a continuance of the process of fermentation: and, ultimately, the acid taste and odour of the vine gar are lost; and the whole mass of the liquor becomes first vapid, and then putrid. That such a process of putrefaction should take place in organised bodies after their death, might in reasoning be antecedently expected; for the purpose of administering to the growth of their successive generations in the case of vegetables; and to prevent the indefinite accumulation of so much dead and useless matter in the case of animals but we could not have anticipated, that, while animal matter at once passes into a state of putrefaction, vegetable matter should previously pass through two intermediate states; accompanied with products which in their nature differ both from each other, and from the source from which they were derived: both, however, as we might very reasonably expect from the known wisdom and beneficence of the Creator, of the highest importance to mankind. From wine, to say nothing of the advantages resulting from its proper use in its common state, is derived that useful fluid called alcohol, or spirit of wine: among the most valuable properties of which, may be ranked its power of dissolving resin, and other vegetable principles; and of preserving organized matter from the putrefactive process. In consequence of the former power, it is employed to extract from various vegetables some of those parts in which their medicinal virtues reside; and to preserve them in a convenient form for immediate use, at any moment, under the technical name of tinctures. And with respect to its importance as a preservative of animal and vegetable matter, but particularly of the former, I need only point out any one of those collections of anatomical preparations_contained in the museums of every medical school in Europe. But if any single instance of its application to this purpose be demanded, who can hesitate to name that astonishing proof of the genius and industry of the great English physiologist, John Hunter, the Collection preserved in the Royal College of Surgeons? on the pedestal of whose bust, placed within the walls of the museum of that college, might well be inscribed, as I believe has been often suggested, those appropriate words, "Cujus monumentum si quæras, circumspice." SECTION V. Vegetables as applicable to the Arts, &c. In considering the application of natural substances to the various purposes of life, it is often interesting to compare the simpli "Haud igitur penitus pereunt quæcunque videntur : city of the orginal contrivance with the complicated manipulations of the process by which, at the present day, a material, destined for a specific use, is brought into a fit state for that use. Let fine writing-paper be taken as an instance; and let us compare the history of a piece of such paper with that of the simple material on which many Oriental manuscripts are written the mere leaf of a tree, probably some species of palm,-which after having been cut into the requisite size and form, seems to have undergone no other preparation than simple pressure; partly with the view of forcing out its natural moisture, and partly of smoothing its surface. How different the history of the paper that is daily fabricated in any of the large manufactories of this country; and how little would its origin and numerous changes of state be conjectured from its present appearance! Heaps of linen rags of every colour, when indeed that colour can be distinguished through the dirt which adheres to them, are brought from almost every quarter of Europe; each rag having probably been part of some article of dress, which as it grew viler by use, passed from a more to a less respectable possessor; till it at length became the tattered and threadbare covering of the poorest mendicant. From such a material is the finest paper made: and, in the commencement of the process, each individual rag undergoes an examination with respect to its size, and is cut into two or more pieces according to that size. Separate heaps are then mechanically shaken together, and sifted, in order to clear them from adhering dust: they are subsequently washed, mechanically divided into small shreds, bleached, then thrown into vats of water, and there reduced to a fine pulp by the application of powerful machinery. This pulp, by very delicate yet simple means, is kept in a state of close and equable diffusion over an even surface, and is made to pass between successive pairs of smooth metallic cylinders; all of which, by pressing out the moisture of the pulp, bring its particles more closely together, and thus tend to give it the requisite degree of firmness and cohesion; the last pair being heated sufficiently to dry the paper during its passage between them. Such are the numerous and elaborate processes, by which a heap of sordid rags is converted into the beautiful material of which we have been speaking. And if, to the accumulated processes to which each rag is submitted during its fabrication into paper, be added its previous history, as the cultivation and subsequent dressing of the flax of which it was made, the formation of the fibre of the flax into thread, the weaving of the thread into linen, and, in the majority of instances, the dying of the linen; if all these points be collectively considered, what food for a reflecting mind does not the minutest particle of the resulting paper afford! Many plants are capable of yielding a colouring matter, which by chemical means may be readily made to combine with various |