The observations of Priestley, Saussure, and others, aided by the discoveries made in pneumatic chemistry, of the existence of oxygen, hydrogen, and carbonic acid gases, formed a new era in the history of vegetable physiology. It was proved that vegetables do ultimately consist of oxygen, hydrogen, and carbon, sometimes of a small quantity of nitrogen, combined with mineral salts, and often some silex, sulphur, and iron. These elementary substances were found to be diffused through air and water, and the animal and vegetable substances which the latter holds in solution: the green parts of vegetables were observed to exhale oxygen in the light, and carbonic acid gas in the dark; and the carbon left by the decomposition of the carbonic acid, was shown to be incorporated into the vegetable substance, giving to the wood its strength and hardness.

66

The naturalist whose labours, in point of utility, will best bear a comparison with those of Linnæus, is Bernard de Jussieu. He was remarkable for the extent of his knowledge, the penetration of his genius, and the solidity of his judgment. He is said to have been unambitious. The love of truth and science were with him sufficient excitements to the most severe labour. Many of our contemporaries," says Mirbel, "knew this sage; they say that never have they seen so much knowledge combined with so high a degree of candour and modesty." To this botanist we are indebted for a natural method of classification, superior to those of his predecessors.

Jussieu proposed a method of classing plants according to certain distinctions in the seed, which were found to be universal; this was perfected and published by his nephew, Antoine-Laurent de Jussieu, and is now generally received as the best mode of natural classification which has yet been discovered. This method is called natural, because it aims to bring into groups such genera of plants as resemble each other in medicinal and other properties; while the system of Linnæus is called artificial, because, by a certain rule, plants which have no such resemblance in their properties are brought together. We therefore find in one of the Linnæan classes the poisonous flag and the nutritious grass, the grain which supports life and the darnel which destroys it; in another, the healthful potato and the poison mandrake, the deadly hemlock and the grateful coriander. Throughout this system we meet with similar contrasts in the qualities of the plants which are collected into the same classes. Nor are their external appearances less unlike; for here the oleander and pigweed, the tulip and the dock, meet in the same classes. This system, it should always be remembered, is not the whole science of Botany, but is the key to the natural method, by which alone, we should find great difficulty in ascertaining the names of plants; it is, as it were, a stepping-stone by which we must ascend to the valuable knowledge which cannot well be reached in any other way. The more practical a botanist becomes, the less need he has for this assistance; the eye becomes quick to seize on natural characters without reference to the dictionary, as the artificial system is aptly termed. Thus a pupil, in studying a language, may, in time, be able to dispense with his dictionary; though he could not have proceeded, at first, without its assistance. For more particular explanations of Jussieu's method, you are referred to the comparison of that with the method of Linnæus and Tournefort in the remarks on classification, and to the Natural Orders contained in the appendix.

Priestley, &c.-Character of Jussieu-Natural method of classing plants.

Adanson, previous to the time of the younger Jussieu, had published a system of classification, in which he arranged plants according to the resemblance observed in all their organs. In one class, all which had similar roots were placed; in another, all which had similar stems; a third was arranged by resemblance of leaves, in their forms and situations; but the most important distinctions he considered as founded upon the organs of fructification. The name of this ingenious botanist is preserved in the Adansonia, or calabash-tree, of Africa, which is considered as the colossus of the vegetable kingdom.

Among other botanists, we would notice Louis Richard, who wrote in French an interesting account of the Orchidea of Europe, and assisted in compiling from ancient works a very useful botanical dictionary.

Des Fontaines first showed that the stems of monocotyledonous and of dicotyledonous plants differ from each other in their structure and modes of growth; he divided them into endogenous, growing inwardly, as the palms, and exogenous, growing outwardly, as the oak.

France is distinguished for the number and accuracy of its naturalists. Mirbel, a distinguished professor of Botany in Paris, has pursued his inquiries into the anatomical structure, and the physical operations of plants, to an extent not exceeded by any other naturalist; his “Elemens de Botanique" is a splendid work, which forms a very important and valuable addition to a botanical library.

The Baron Humboldt spent five years in investigating the vegetable productions of the equatorial regions in America, and his remarks on vegetables, as a criterion of climate, are original and interesting.

Josephine, the first wife of Napoleon, was distinguished for her fondness of this study; other ladies of distinction, stimulated by her example, cultivated plants with reference to scientific observations. In England, Mrs. Wakefield, and the industrious and enlightened Mrs. Marcet, (author of Conversations on Natural Philosophy, Chemistry, &c.) have distinguished themselves as the authors of useful treatises on Botany.*

De Candolle's "Elementary Theory of Botany," is highly valued as a scientific and able performance; but it is useful, rather for those who have already attained a knowledge of the elements of Botany, than for the beginner in the science. The natural method of Jussieu has been modified and improved by the labours of De Candolle, Mirbel, Lindley, and Robert Brown.

In turning from Europe to the United States, we find the state of literature flourishing, and a taste for the natural sciences becoming extensively diffused. The names of many of our scientific men stand high in Europe, as well as in their own country. Among these are Silliman, who established the first scientific journal, and encouraged others to pursue the course of investigation which he himself has followed so successfully. Eaton has laboured to bring science within the reach of every inquirer; not only by rendering the

* Mrs. Somerville, from the extended views of science which she has exhibited, may, perhaps, be called the scientific woman of her age.

+ Except the Mineralogical Journal of Bruce, which ceased after the appearance of a few numbers.

Adanson-Richard-Mirbel-Humboldt-Females who have interested themselves

in the study of Botany-De Candolle-Silliman-Eaton.

labours of others of more general utility, but adding to the common stock the result of years of inquiry and observation.

To go back to the infancy of Botany in the United States, we find the name of Bartram stands recorded in history, as that of the first native of our country who was conspicuous for botanical researches. Houston investigated the region of Canada, and described many of its plants; in honour of him is named the little flower HOUSTONIA cærulea, which is abundant in New England. Clayton made a list of Virginian plants, and is commemorated in the beautiful CLAYTONIA virginica. Kalm, a pupil of Linnæus, whose name is given to the KALMIA, (American laurel,) spent three years in America, and returned to Europe laden with botanical treasures; the sight of the American plants brought by his pupil, many of which were entirely new to him, is said to have produced such an effect upon Linnæus, that although lying ill of the gout, and unable to move, his spirits were rekindled, and in the delight of his mind he forgot his bodity anguish, and recovered from his disease.*

Although American works on Botany are not wanting, the author of these Lectures found no one book, either foreign or American, which seemed designed to conduct the pupil through a full and connected course of study. To bring together in one volume the Elements of Vegetable Anatomy and Physiology, the principles on which the Natural and Artificial Classification depend, and to teach these systems by a full exposition of them, and by a Flora of Plants, for practice in analytical Botany-these have been the objects in view in the preparation of this work. Its publication, we hope, has removed the obstacles which formerly impeded the progress of botanical information, in schools, and among our own sex. We have seen that even children may become botanists, and lay aside their toys to divert themselves by distinguishing the organs of plants and tracing out their classification.

Of all sciences, perhaps no one is settled on a firmer foundation

* Among the earliest botanists of North America, were Colden, Michaux, and Muhlenberg; Pursh was the first who finished a system of North American plants, so arranged as to be useful to the student. Some of the first teachers of the science were Barton, Hosack, and Mitchill. The first public lecturer on Botany, was Professor Amos Eaton. Dr. Bigelow gave a course of lectures in Boston, in the year 1813, and soon after published his Boston Flora. Professor Ives and Dr. Tully did much in New England towards awakening a zeal for the science, in the years 1815 and 1816; and at a later period, Dr. Sumner has pursued and illustrated the study with much ardour and success.

Want of books was a great impediment to the progress of the science when Eaton published his Manual of Botany; this book gave a new impulse to the progress of the science; its familiar method and simple style induced many to commence the study. This was followed by many other works describing plants, and several elementary works; of the former class were Nuttall's Genera, Elliott's Southern Plants, Barton's Flora of Philadelphia, Darlington's, Torrey's, and Bigelow's Floras; these furnished descriptions of most American plants, not included in the works of Pursh. Among Elementary books are Barton's Elements," a large work containing much that is interesting in the physiology of Plants; 'Lock's Botany," a small book, but exhibiting a plan of arrangement simple and methodical; Sumner's Compendium of Botany," written in a beautiful and pure style; and more recently, "Nuttall's Elementary Work," which gives in popular language more facts with regard to plants, than almost any other work of the kind; a small work entitled "Catechism of Botany," by Miss Jane Welsh, was the first attempt by an American lady to illustrate the science. Professor Lindley's late work, entitled "Introduction to the Natural System of Botany," though it may be highly useful to the advanced student, cannot be studied with advantage except by the practical botanist. Beck's Botany is a neat and beautiful introduction to the natural system, and his descriptions of Genera and Species are valuable.

Bartram, and some others-Houston-Clayton-Kalm-Objects of this work.

than that of Botany; the improvements of future years, we are not able to anticipate; but it is probable that as discoveries and improvements are made, they will cluster around the principles already established; each taking its proper place in the various departments now arranged for the reception of scientific truths.

The spirit of our government is highly favourable to the promotion and dissemination of knowledge; and although Europe may boast of many stars which irradiate her firmament of letters, shining with brilliant lustre amidst the surrounding darkness of ignorance, may we not justly feel a national pride in that more general diffusion of intellectual light, which is radiating from every part, and to every part of the American republic!

LECTURE XLVI.

GENERAL VIEW OF NATURE-ORGANIZED AND INORGANIZED BODIES-CLASSIFICATION OF ANIMALS.

HAVING Considered the vegetable kingdom under its various aspects, it may be proper, before closing our course of botanical study, to take a general view of that external world of matter, of which the part we have examined, extended and diversified as it is, constitutes but a very small portion. The science you have been investigating, with some others, constitutes a general branch of knowledge termed Natural science. The study of nature presents, in a lively and forcible manner, the power and wisdom of the Creator; and offers to the enlightened mind, a never-failing source of the most pure and refined enjoyment. Those who know nothing of this source of happiness, cannot appreciate its value; they may inquire the use of studying into the nature of objects, without any reference to the enjoyment of the senses, to personal gain or honour. A celebrated naturalist* observes: "The rich and the great imagine, that every one is miserable, and out of the world, who does not live as they do; but they are the persons who, living far from nature and from God, live out of the world. Misled by the prejudices of a faulty education, I have pursued a vain felicity amid the false glories of arms, the favour of the great, and sometimes in frivolous and dangerous pleasures. I have never been happy but when I trusted in God: opposed to THEE, the AUTHOR of all things, power is weakness! supported by THEE, weakness becomes strength! When the rude northern blasts have ravaged the earth, THOU callest forth the feeblest of winds; at the sound of THY voice, the zephyr breathes, the verdure revives, the gentle cowslip and the humble violet cover the bosom of the bleak earth with a mantle of gold and purple."

To the pious reflections of this French writer, we will add the following quotation from an English author,† the energies of whose rich and cultivated intellect were devoted to the cause of religion, who viewed nature as a philosopher, but what is far better, as a Christian. Happy indeed, are those in whom philosophy and Christianity are blended, and delightful is the intercourse, even in this world, between minds thus enlightened and purified!

* St. Pierre.

+ Rev. Legh Richmond.

Science of Botany settled-Difference between the state of science in Europe and America-Natural science-Reflections on the study of Natural science.

"There is a peculiar sweetness in the recollection of those hours which we have spent with friends of a kindred spirit, amidst the beauties of created nature. The Christian can alone find that congeniality in associates, who not only possess a lively and cultivated sense of the high beauty which landscape scenery presents to the eye, but who can also see creation's God in every feature of the prospect. The painter can imitate, the poet describe, and the tourist talk with ecstacy of the sublime and beautiful objects which constitute the scene before him; but he can only be said to enjoy them aright, whose talents, taste, and affections are consecrated to the glory of Him by whom all things were made, and without whom was not any thing made that was made.' When the pencil that traces the rich and animated landscape of mountains, lakes, and trees, is guided by a grateful heart as well as by a skilful hand, then the picture becomes no less an acceptable offering to God, than a source of well-directed pleasure to the mind of man. And when the poet, in harmonious numbers, makes hill and dale responsive to his song, happy is it if his soul be in unison with the harp of David, and if he can call on all created nature to join in one universal chorus of gratitude and praise. The Christian traveller best enjoys scenes like these. In every wonder he sees the hand that made it-in every landscape, the beauty that adorns it-in rivers, fields, and forests, the Providence that ministers to the wants of man-in every surrounding object he sees an emblem of his own spiritual condition, himself a stranger, and a pilgrim, journeying on through a country of wonders and beauties; alternately investigating, admiring, and praising the works of his Maker, and anticipating a holy and happy eternity to be spent in the Paradise of God, where the prospects are ever new, and the landscapes never fade from the sight!"

"Oh! for the expanded mind that soars on high,
Ranging afar with Meditation's eye!

That climbs the heights of yonder starry road,
Rising through nature up to nature's God.

"Oh! for a soul to trace a Saviour's power,

In each sweet form that decks the blooming flower:
And as we wander such fair scenes among,,

To make the Rose of Sharon all our song.'

Naturalists, to the great discredit of science, have formerly shown an unhappy tendency to skepticism; enabled to comprehend some of the great operations of nature, they presumed to set up their own reason against the revelation of God, and impiously refused to believe any thing which could not be explained according to the principles of human science. Searching into the elements which compose the human body, and observing the dispersion of the same, and their incorporation into other substances, they affirmed that it was "a thing impossible for God to raise the dead." Well might we, in addressing such a philosopher, say, with the Apostle, "Thou fool!" Cannot he who formed all things of nothing, reanimate the sleeping dust, and recall the spirit to its own body? Happily, this melancholy perversion of human learning seems to have passed away, and we now see many of the most enlightened investigators of the principles of science among the most humble disciples of Jesus.*

In the character of Dr. Mason Good, as exhibited in his biography, written by Olinthus Gregory, we find this union of science with deep and fervent piety most happily exemplified.

Naturalists formerly inclined to skepticism.