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examine; not, however, expecting to decide upon subjects which lie hidden from the researches of finite beings; but the rather to show you, that the "ways of the Almighty are unsearchable, and past finding out !"
After what has been remarked upon the difficulty of analyzing the plants belonging to the Crytogamous class, you will not need to be discouraged, should you be baffled in your attempts to investigate them. It is well for mankind that there are philosophers, whom the enthusiasm of scientific pursuits will lead to spend years, even a whole life, in searching into the fructification of a moss or mushroom; or in examining into the natural history of an ant or a spider ;* as thus, discoveries are continually brought forward, which add to the general stock of knowledge. This is a kind of martyrdom in the cause of science to which but few seem called, by the powerful impulses of their own minds. Females, in particular, are not expected to enter into the recesses of the temple of science; it is but of late, that they have been encouraged to approach even to its portals, and to dare to glance upon the mysteries within.
We have now completed our view of the vegetable world, according to the order in which the different tribes of plants have presented themselves. As we followed in the train of classification, we have endeavoured to notice the most conspicuous, and to trace their natural relations, as well as their artificial arrangement.
In many cases, departing from the plan of general remarks, we have traced the natural history of some one genus, believing this method more likely to make a permanent impression, than merely general views. When we read the history of nations, we often feel less intérested in the fate of a whole people, than in that of some prominent individual: if the imagination is presented with general ideas only, it has no opportunity of fixing itself upon any single circumstance in order to create a lively picture in the mind. The same remark may apply to natural history. When you now look back upon the view just taken of the vegetable world, and examine what impressions are most lively in your minds, you will probably find them to be respecting some peculiarities of individual plants. Of this tendency of the mind we should avail ourselves, by connecting these particular impressions with facts which lead to general
I have been gravely assured by a naturalist of distinction, that the study of spiders is one of the most elegant and delightful of all pursuits.
Enthusiasm of some naturalists-View of Classification completed-General ideas make little impression on the mind-Tendency of the mind to generalize.
principles. Narrow indeed, would be our mental vision, were it to be confined to single unconnected observations, laid up indiscriminately in the storehouse of thought; but our minds, not by our own will, but by a faculty received directly from our Creator, instinctively generalize and arrange their mass of single observations; and we almost without an effort, perform that operation in the world of thought within us, which the great Linnæus effected in the vegetable kingdom.
On entering the fourth division of our course, we find before us an open field, freed, in a great measure, from the technicali ties of science, and presenting a smooth and delightful path. Hitherto, we have been clearing our way through difficulties, and overcoming obstacles; first, we were obliged to learn to analyze plants according to the strict rules of botanical science; next to examine the organs of plants, with their anatomy and physiology; we then investigated the principles of classification, as exhibited both in the natural and artificial methods, and followed the arrangements of plants as presented in these different methods.
The language of botany is now familiar to you, and you may enjoy the pleasant reflection, that by your own industry and application, you have elevated your mind to that state, in which it may with little farther effort enjoy the pleasant views of the vegetable kingdom which now present themselves. Thus the traveller, having toiled to gain some acclivity, looks complacently around, enjoying the beautiful view before him, in proportion as he has made efforts to attain it.
We will now suppose the dreary season of winter, yielding to the gentle influences of spring, and organized nature awaking to new life and beauty; for animals, no less than plants, seem vivified and quickened by the returning warmth of this delightful season. How many, wandering through life "with brute, unconscious gaze," have never made the inquiry, "what causes Spring?" With the greater part of mankind the ordinary phenomena of nature excite no interest; it is only when something unexpected occurs, that they think, either of first or second causes. But it is the main object of your education to teach you to reflect, to seek the connexion
Remarks introductory to the fourth part-What causes spring?
between causes and effects; and especially to look through second causes, to the Great Being who is the First Cause of all; "himself, uncaused."
But to return to the question, "what causes Spring?" or to state it in another form, by what means does the Almighty produce the changes which this season presents? To answer this, we must refer to astronomical geography, which, pointing out the course of the sun, shows us that having journeyed to his utmost southern boundary, he returns, crosses the equator, and with rapid strides advances towards the northern hemisphere, beaming more directly upon us, and increasing the temperature of the atmosphere; to chemistry we owe our know. ledge of the effects of caloric on bodies; physiological botany shows us the sap or vegetable blood expanding by the influence of caloric, and every exhaling and inhaling organ of the plant commencing operations under the same powerful influence. The earth, released from the icy bonds of frost, turns kindly to the mute, but living children of its bosom, and imparts the maternal nourishment, which, rushing through every fibre of the vegetable being, invigorates it with health and strength.
From the first appearance of vegetation in the spring, until the commencement of winter, nature presents an ever varying scene. The phenomenon of the flowering of plants,* is in many respects, similar to that of the putting forth of leaves ;† in both, the same causes either hasten or retard this period. The putting forth of leaves, and the blossoming of flowers, differ however in one circumstance; the leaves begin by the upper leaf buds; the flowers by the lower flower buds; stipes, panicles, and thyrses begin to blossom gradually from the base to the summit. Cymes and umbels blossom from the outside to
In plants of the north, transported to the south, the period of the putting forth of leaves and blossoming is hastened; in those of the south, carried to the north, it is retarded. Even in their native soil, this period varies in some degree in different seasons. With greater warmth of temperature, we have an earlier appearance of vegetation; yet in general, this variation is so slight, that botanists are able by observation, to fix with a sufficient degree of accuracy, the time of the flowering of plants in particular latitudes and climates.
The progress of vegetation varying little from Latitude 40° to 43° north, the remarks that we make on this subject, may
Changes in vegetation-Putting forth of leaves and blossoming of flowers agree in some respects, differ in others-Plants of the north transported to the south, and the reverse-Remarks on the progress of vegetation; to what extent of country applying.
apply to that region of country extending south to the mouth of the Hudson, north to the mouth of the Mohawk, eastward to the Atlantic, and westward to the Pacific Ocean.
In Ohio, and the western part of New York, the climate, on account of the influence of the lakes, and the cold, eastern winds from the Atlantic being broken by ranges of mountains, is milder, and vegetation is somewhat earlier than in New England in the same latitude.
In some cases, a plant puts forth leaves and blossoms at the same time; but usually, the leaves appear before the flowers, probably having a greater force to draw up the sap than the flowers, in which it rises by slow degrees. We see little appearance of vegetable life as early as March; sometimes snow covers the ground nearly or quite through the month; but if we examine the trees and shrubs, even then, we may perceive that they have already felt the vivifying influence of heat, by the swelling of their buds, and that a little increase of temperature will cause the embryo flower, or leaf, to burst its prison and come forth.
In April, the leaves of trees and shrubs begin to put forth; a few flowers show themselves, amid the damp chilly atmosphere with which they are surrounded; among the most interesting of these harbingers of spring is the HEPATICA triloba, or liver-leaf; a lowly, modest flower, of a pale blue colour, with beautifully formed three-lobed leaves.
The low anemone (ANEMONE nemorosa*), with its pale blossoms, is now found in shady woods and damp pastures.
Among the blossoms now to be seen are most species of the poplar, a plant in the class Monacia, having stamens and pistils on separate plants. The salix, or willow, is of the same class: this genus includes the weeping willow, or SALIX_tristis,† sometimes called Salix Babylonica, in allusion to a beautiful passage in the psalms, which represents the children of Israel when carried into captivity, as sitting down by the waters of Babylon to weep, and hanging their harps on "willow trees that withered there."
Among the forest trees now in blossom, are the maple and the elm; in the meadows and moist grounds, the yellow cow
*This little flower I have seen raising its head amid surrounding snows, on the banks of the Poesten kiln, a romantic little stream which flows into the Hudson, near Troy.
+ Tristis (Latin) signifies pensive or sad.
Vegetation in March-Flowers of April.