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moral world, while nature had moved on in her unchanging course? History is silent! But while in the old world empires had been rising, continuing for centuries stationary, and then decaying; succeeded and succeeded by others pursuing the same track: were no changes going on in the American continent? Had no mighty nations ever existed here? Had no arts or letters been cultivated? Had the savage Indian for thousands of years been sole lord of one half of the world? And when, and how, did the first inhabitants of this continent come from Asia, where man was placed at his creation? These are inquiries which naturally arise, on tracing the historic page through so long a period of time, until suddenly this new world bursts upon our vision ! But, although many speculations have from time to time appeared, respecting the probable history of America, all, until its discovery by Columbus, remains a sealed book.
History of Botany, from the beginning of the sixteenth century to the time of Linnæus.
We have now traced the progress of botanical knowledge from the earliest periods of the world to the discovery of America. About this time Botanic gardens began to be cultivated: these afforded new opportunities for investigation, by comprehending the vegetables of all countries within such limits as enabled the botanist to compare them; and to watch their growth and different stages of developement.
From the days of Theophrastus until the beginning of the 16th century, botany, instead of becoming more perfect, had been rendered more obscure. This was not owing to want of attention or labour, but to the false rules of philosophy which had so long prevailed.
At length the cause of the evil seemed to be discovered. Many writers protested against the erroneous opinions of their times; they said, "our blind respect for the ancients is an insurmountable obstacle to the progress of botany. We expect to find every where the plants of Theophrastus, Dioscorides, and Pliny; whereas they did not know one hundredth part of the plants which cover the globe. The first of them never went out of Greece; the second left only unconnected notes,
Botanic gardens first cultivated-Botanists began to discover obstacles to the progress of the science.
treating without order upon the medicinal qualities of plants; and Pliny copied these notes without comment or criticism. We cannot apply to the plants of Germany or France, the names under which the ancients described those of Italy, Greece, and Asia: before studying the plants of foreign coun tries, we ought to know those of our own. Of what use are disputes about the nature and qualities of species, when we are not able to distinguish one from another. The true method of doing this is to explore the plains, valleys and mountains, to examine and compare the plants of our own and foreign countries. Libraries alone are insufficient to make botanists."
These reflections led to a happy revolution, not only in this science, but in all others; it may be called the era of true philosophy.* Yet the principles, which were now discovered, were not much applied to science until the time of Bacon, Newton, Linnæus and Locke; and it remained for the late Thomas Brown, of Edinburgh, to show that the human mind itself, is subject to the same general laws of inquiry which now regulate investigations in the physical sciences.
Up to the period of which we are now speaking, plants had only been described in alphabetical order; about this time some German botanists attempted a collection of individual plants into species; this improvement was received with much. approbation.
These species were arranged according to certain general resemblances, or natural relations; thus we see that natural methods were prior to any attempts at an artificial system.
In the beginning of the 16th century, we find the names of many who were engaged in investigating the vegetable kingdom. Some are commemorated by the names of plants; Leonard Fusch of Germany, by the plant Fuschsia; Lobel, physician to James I. by the Lobelia; and Lonicer by the Lonicera.
Lobel distinguished the cotyledons of seeds, and divided monocotyledonous, from dicotyledonous plants, and attempted to form families by grouping species according to their natural
*Lord Bacon is generally considered as having first taught the proper method of studying the sciences, viz: by ascending from facts to principles; this is called the method of induction. It has recently been asserted by an able writer in one of our first American periodicals, that Bacon was not the author of the inductive philosophy, but that he borrowed his rules of philosophizing from Aristotle, whose real principles had for ages been misunderstood. It is to be hoped that men of talents will not so far depart from the true rules of philosophizing, as to devote that time in contending about their author, which might be profitably applied in the application of these rules to the investigation of
Era of true philosophy-Improvements of German botanists-Botanists of the 16th century.
relations. Zaluzian of Bohemia laboured to perfect the natural groups of former botanists; he is the first of the moderns who positively affirmed the existence of stamens and pistils in all species of plants, and suggested the necessity of these organs.
But, notwithstanding the labours of many learned men, little real improvement would have been made in the science of botany, had there not, at that time, existed some minds of superior genius, who turned their attention to tracing some proper method of classification. These were Gesner, Clusius, Cæsalpinus, and Bauhin; of the latter name were two brothers, both of whom are deservedly celebrated.
Gesner, a native of Switzerland, born in 1516, was of an obscure and humble origin, but possessed of a powerful and penetrating mind. He attempted to make a general collection of the objects of Natural History; he explored the Alps, and discovered many plants until then unknown. He is distinguished from those who had gone before him, in his suggestions that there existed in the vegetable kingdom groups or genera, each one composed of many species, united by similar characters of the flower and fruit. Soon after the publication of this opinion, botanists began to understand that the different families of plants have among themselves natural relations, founded upon resemblances and affinities, and that the most obvious are not always the most important. These are fundamental truths; and the distinction of species, the establishment of genera, and of natural families, seemed to follow of course after these principles were once established.
Clusius was born in 1526; his parents had destined him for the profession of law, but his decided taste for botany induced him to abandon this profession. He was learned in the ancient and modern languages, but his enthusiasm for natural history induced him to lay aside every other pursuit. He travelled over almost all the west of Europe, in order to make discoveries in the vegetable kingdom; and soon excelled all the botanists of the age in the knowledge both of native plants and exotics. He had the direction of the imperial garden at Vienna, and afterwards was a public professor of botany at Leyden. His passion for the study of plants was not enfeebled by age or infirmities; his enthusiasm in this science terminated only with his life. Before his time, the art of describing plants with precision and accuracy was unknown; but unlike the descriptions of his predecessors, his were neither faulty
Gesner-How distinguished from his predecessors-Clusius-the first who proposed to divide plants into classes.
from superfluous terms, nor from the omission of important circumstances.
Cæsalpinus, a native of Florence, who was contemporary with Clusius, proposed to form species into classes. The characters which he employed for this purpose, were, the duration and size of plants; presence or absence of flowers; the number of cotyledons; the situation of the seed as erect or pendant; the adherence of the pericarp to the seeds; the number of cells in the pericarp, and the number of seeds which they contained; the adherence of the calyx to the germ; and the nature of the root, whether bulbous or fibrous. This method was too imperfect to be followed, having neither the simplicity or the unity to render its application useful.
John Bauhin, though younger than Gesner, was his friend and pupil; he composed a general history of plants; this was a work evincing great learning and accurate investigation. Gaspard Bauhin, the younger brother, no less active and learned, and endowed with a still more penetrating genius, conceived the design of a work which should contain a history of all known plants, together with the different names which other writers had applied to the same plant. Clusius and the elder Bauhin had imagined something like a genus of plants, formed by the grouping of similar species, but Gaspard Bauhin expressed this more decidedly in remarks upon generic distinctions; his work, the result of forty years' labour, was of great assistance to Linnæus, in perfecting our present system of botany.
We find in looking back upon the labours of botanists during the 16th century, that more had been accomplished than during any former period; the character of novelty and originalty exhibited in these researches, is highly creditable to those who thus led the way in the march of improvement.
The 17th century, in its commencement, was not favourable to the sciences. Europe was agitated by continual wars, and the arts of peace were neglected; but in the last part of that age, a taste for natural history revived; men of highly gifted minds applied themselves to the study of botany, and many undertook long voyages with the sole design of examining foreign plants. Botanists were astonished at the great number of interesting plants discovered by travellers, in the region of South Africa, around the Cape of Good Hope, and in the East India Islands.
At this period the plants of our own country began to excite
Casalpinus-Characters employed by him in the formation of classes-The Bauhins-Retrospect of the 16th century-Commencement of the 17th century-Last part of that age.
the curiosity of scientific Europeans. Among the number of voyagers to America, was a Roman Catholic Priest, Plumier, celebrated for his mathematical and botanical knowledge; he made three voyages, and gave drawings and descriptions of more American species than any other traveller had done.
We now find many who were distinguished by their efforts in the cause of science, but a notice of each individual would carry us beyond our limits, and prevent that clear conception of the state of the science, which attention to a few conspicuous facts may produce.
Botanists now began to observe the stamens and pistils of plants; it was suggested that the science would remain imperfect as long as species and genera were undefined. Orders and classes also were recommended. Natural resemblances and affinities were studied. A work was written upon the umbelliferous plants ;* it was the first attempt at describing in one mass, any single group of plants by characters peculiar to the whole. This was followed by several attempts to form a natural method of classification; among the most approved of these methods was that of Ray, who published a work called "A General History of Plants;" in this he divided all plants into 33 classes, 27 of which were composed of herbs, the rest of trees.
The first botanist who thought of classing plants without any reference to their being either herbs or trees, was a German, of the name of Rivinius, who proposed to consider as the foundation of classification, the absence or presence of flowers; the manner in which they were situated, or their inflorescence; the number of petals; the regular or irregular form of the corolla; the adherence or non-adherence of the calyx to the germ; the nature of the pericarp; the number of seeds; and of cotyledons.
A botanist of the name of Magnol, at this time was honoured by having his name given to the splendid Magnolia, an American plant, which then began to be known in Europe.
Joseph Pitton de Tournefort, was born in 1656. While very young, he discovered an enthusiastic fondness for botanical pursuits; he had been destined, by his friends, for a profession; but his genius seemed so strongly bent upon the study of nature, that he was at length permitted to indulge without restraint in his favourite pursuits. He ranged over the Alps
*The author of this was Robert Morrison, a Scotchman. These monographies or descriptions of single families, are now of great value; no botanist can thoroughly investigate the whole vegetable kingdom, but by close attention to one department, important discoveries may be made.
Various improvements in botany-Ray-Rivinius-Magnol-Tournefort,