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BOTANICAL SCIENCE. ARTHUR HENFREY, in a Lecture before the London Society of Arts, advocates the claims of Botanical science for public schools:
The most remarkable of the classifications of the sciences which have been given to the world, may be briefly characterized by arrangement under three heads, indicating the totally distinct points of view from which they set out:
1. Those based upon the sources of knowledge. 2. Those based upon the purpose for which the knowledge is sougn.; and 3. Those based upon the nature of the objects studied.
1. The classifications of the first kind, -those which arrange the various branches of knowledge according to the character of the intellectual methods and processes by means of which thev are cultivated, are termed subjective, as regarding alone the nature of the recipient mind, or subject.
If we disregard the technicalities of metaphysics, or rather psychology, we may conveniently restrict our analysis of this, to the distinction of two qualities, those of perception and reflection.
By perception, by the aid of the senses, we observe facts: these facts may be either independent of our influence, when we call the observation proper; or they may be the result of special contrivance on our parts, when the mode of observation is called experimentation; and, again, we may receive information of observed facts by testimony of others. All these processes involve the acquisition of experience, direct or indirect, of phenomena ; the sciences pursued especially by their means are called experimental, and the truths of experience are facts.
Reflection is the action of the reasoning faculty, according to its own laws, upon the simple ideas furnished by perception, dealing with certain properties of these, which it abstracts from the facts of perception, and, by the comparison and classification of them, arriving at generalizations, principles, laws, and the like, known by the collective name of theory. Those sciences which depend almost entirely upon the reason, are called rational, alstract, or theoretical.
Now, when we consider that there exists no science purely abstract from its origin, and that the measure of advancement of every science in the degree to which it has co-ordinated the ideas with which it deals under general propositions and laws, it becomes obvious that the division into experimental and abstract is totally inapplicable to the existing state of science.
2. The classifications according to purpose, the division into speculative and applied or practical sciences, fail almost in the same way, since the progression of every science is marked step by step, by the removal of certain truths from the position of abstract theories, interesting only to the learned, into the rank of axioms from which practical results of the greatest value are derived,
3. The third point of view is that from which we regard only the objects of our study, without considering either the faculties or processes by which we ob. tain our knowledge, or the advantages we may derive from its acquisition.
When we reflect upon the ordinary operations of our reasoning faculties, upon the common rules of logic, it becomes evident that this last mode of classification is the only one that can be called rational, since it is the only one which proceeds, accordin; to the indispensable rule, of advancing from the most simple to the more complex of the ideas, which we wish to co-ordinate in our minds. The other two modes, the division into experimental and rational, abstract and applied sciences, must not only, from their nature, continually shift their ground as knowledge progresses, but they both set out from considerations of a highly complex character, which it would be vain to attempt to analyze, until a very large portion of the whole field of human inquiry has been cleared.
The principle is laid down by Descartes in his “Method,” in the following terms : -" To conduct my thoughts in order, commencing with the objects which are simplest and easiest to know, so as to rise gradually to the knowledge of the more compound ;" and in a subsequent chapter he traces the course of his inquiries through mathematics, general physics, botany, zoology, and the sciences relative to man, according to the progressive complexity of the subjects.
In the chain or series thus formed, there not only exists a logical sequence, å relation of progression of the number of kinds of ideas with which we have to deal, but there is a relation of dependence, insomuch that each science rests upon that preceding it for a certain proportion of its data, and in turn constitutes the necessary basis for that which follows,-added to which we find the history of the development of the individual sciences bringing a striking confirm. ation of the validity of the principle, by showing that, although the first steps were made almost simultaneously in all the great divisions of science here laid down, the most simple have, from their nature, outstripped, in exact proportion to their relative simplicity, those which involve more complicated classes of gencralities ; so that, as it has been well expressed, the logical antecedents have always been the historical antecedents.
The objective classification of the sciences may be briefly explained here.
The primary divisions depend upon the groups or classes of truths, which must be arranged according to their simplicity, or, what amounts to the same, their generality: in other words, the small number of qualities attached to the notions with which they deal.
The mathematical sciences deal with ideas which may be abstracted entirely from all material existence, retaining only the conceptions of space and number.
The physical sciences require, in addition, the actual recognition of matter, or force, or both, in addition to relations in space and time, but they are still confined to universal properties of matter.
The biological sciences are distinguished, in a most marked manner, by their dependence; the laws of life relate to objects having relations in space and time, and having material existence; they display, moreover, in their existence, a dependence upon physical laws, which form their medium; but they are distin. guished by the presence of organization and life, characterized by a peculiar mobility and power of resistance to the physical forces, and an individuality of a different kind from that found in inorganic matter.
The sciences relating to man, to human society, are removed another step, by the interference, among all the preceding laws, of those relating to the human mind in its fullest sen se. We thus obtain four groups. The following table illustrates these remarks :Abstract or absolute,
to Matter, Physical Sciences.
to Life, Biological Sciences.
to Man, Social Sciences. These four groups include respectively a number of secondary sciences derived from, dependent on, or forming essential constituents of the groups. With these we shall only so far engage ourselves here as relates to the subdivisions of biological science. Certain common characters run through these, life and organization being attributes of all the objects with which they are conversant. Physiology and morphology traverse the whole field of organic nature, animal as well as vegetable. But as animals and vegetables exhibit, in mass, a manifest difference in the degree of complexity of the vital powers and the organization,since the animal kingdom exhibits qualities which are superadded to, and conjoined with those which it shares with the vegetable kingdom,-it becomes necessary to distinguish the branches of biology relating to these, and to divitle these sciences under two heads, Botany and Zoology.
The greater simplicity of the physiological processes of vegetables, is alone sufficient to indicate their inferiority, or antecedent position in the scale of natural objects; and this is further confirmed, in accordance with the principle of objective classification, by their greater generality, since they extend through the succeeding group, in the vegetative or organic life of animals, while the animul life proper is restricted to the latter. And this physiological distinction is in agreeinent with a morphological or anatomical difference ; for not only is the apparatus of organic life more complicated in animals, but these possess a system of organs, the nervous system, which is not represented in any way in vegetables, and constitutes the especial instrument or seat of that kind of spontaneity which is the most striking characteristic of animal life.
We will now direct our attention to some further considerations regarding the relations of botany, as one of the biological sciences, to those preceding it in the classification we have adopted. That branch of physics which immediately precedes it is chemistry, the most special of the physical sciences, and its relations with this it will be sufficient for us to examine among the antecedents.
Chemistry, like the biological sciences, penetrates into the intimate constitation of natural bodies, and moreover, the bodies subject to its domain exhibit a kind of individuality not dependent upon ideas of number, density, color, &C., alone, but upon this said intimate constitution. We arrive here at the formation of certain abstract notions, for the purpose of classitication, which include in the particulars from which they are derived, both statical and dynamical characters. These abstractions refer to the idea of a species, which, however, is far more general here than in botany or zoölogy. A species in chemistry is a definite compound of two or more elements, in obedience to certain general laws, possessing certain definite characters, by which it may be known froin all other species; the relation between the objects represented in this conception is one of identity in all respects but that of simple material continuity; the individuality of separate natural objects belonging to the given species depends solely upon their being mechanically separated from each other. There do indeed exist varieties in chemical species analogous to the varieties of species in living nature, but these partake of the same unstable individuality, and depend upon physical causes of great generality. Thus the allotropic conditions of some chemical substances, and even perhaps the crystalline or amorphous states of many, may be regarded as varieties of this kind. These species are remarkable, not only from the generality of their nature but from their immobility. The only possible change in a chemical species is its conversion into other species, or transformation, in which the relations become entirely changed, and the name altered. There is nothing like development here,-the gradual unfolding by assimilation and transformation of material received from without.
In the organic kingdoms the idea of the species is an abstraction from very different facts. The objects to which it refers have a separate individuality, dependant upon characters non-existent in inorganic bolius. They are incapable of transformation, but susceptible of change according to certain laws; and while the chemical individual is homogeneous, and can only be divided into parts, of which each equally well represents the species, the biological individual is divisible in parts of different kinds, which have relations of harmony and continuity, but by no means of homogeneity, these parts making up together what constitutes the organism. Thus we see a distinct gradation between chemistry and biology, in reference to the generality of the notion which forms the basis of all classification in each.
In biology itself we find that the notion of the individual is modified in an analogous manner, when we carry it up from the vegetable into the animal kingdom; at all events, in those subjects of the latter, in which animality is most clearly manifest. In regard to taxonomy, then, or classification, botany stands between chemistry and zoology.
As the taxonomy, or the classification of plants, is that department of botany which gives it a special utility as a means of mental training; as it is on this ground, above all, that it founds a claim to form a part of general education, it may be permitted me to enter into some technical details here, to illustrate and enforce the propositions just laid down. In the first place, the terminology of botany demands attention. It is a fundamental condition of the existence of organography, that the botanist should possess a rigidly defined technical language, a store of descriptive terms, sufficiently copious, to denote every part and every quality of the parts of plants by a distinct name, fixed, and unalterable in the sense in which it is employed. The technical language of botany, as elaborated by Linnæns and his school, has long been the admiration of logical and philosophical writers and has indeed been carried to great perfection. Every word has its definition, and can convey but one notion to those who have once mastered the language. The technicalities, therefore, of botanical language, which are vulgarly regarded as imperfections, and as repulsive to the inquirer, are in reality the very marks of its completeness, and far froin offering a reason for withholding the science from ordinary education, constitute its great recom. mendation, as a method of training in accuracy of expression and habits of describing definitely and unequivocally the observations made by the use of the senses. The acquisition of the terms applied to the different parts of plants exercises the memory, while the mastery of the use of the adjectives of termin. ology cultivates, in a most beneficial manner, a habit of accuracy and perspi. cuity in the use of language. What is called the nomenclature of botany refers to the names given to the abstract notions of the kinds of beings dealt with in classification to the species, genera, families, and so on. These refer not merely to the possession of particular attributes, but carry with them the idea of those attributes being distinctive of a kind of things; that is, they carry with
them not only their definition founded upon qualities, but the idea, superadded to their definition, that these qualities are characteristic of an abstraction.
In the first place, it must be evident to every one that the general physiology of plants (which presupposes a knowledge of the physical and chemical laws influencing them), together with the concrete natural history of the species dealt with, must form the only secure basis of scientific agriculture; that it has not been fully recognized as such hitherto, depends upon its inevitable imperfections, which, however, will be the sooner removed, in proportion as agriculturists devote themselves to the study of physiological laws.
Secondly, botany finds a place in the two cosmological sciences studying the past and present conditions of the globe-Geology and Geography.
The perishable nature of vegetable structures does, indeed, render fossil remains of plants less valuable as objects for palæontological reasonings, than the better-preserved hard parts of animals, especially as the latter afford safer grounds for estimating how much has been lost, how much preserved, of ancient forms of organization. But botanical reasonings form an e sential link in geological inductions, althongh it is requisite to be very careful in applying the analogical method, derived from classification, to the history of the development of the organic creation.
In geography, that is, physical geography, the concrete natural history of plants becomes a portion of the concrete natural history of the globe ; the physiological laws are involved with physical laws of climate, soil, &c., in the explanations of possible distributions, either in an abstract point of view, or for the purpose of practical application; while the systematic classifications, and tho natural history of particular species, become the only guide by which we can attempt to trace back the existing conditions of distribution towards their origin, and thus perform the share due from botany; in the historical connection of physical geography with gcology, of which it is properly only the statical part.
Pror. J. IIOOKER, Director of the Botanical Gardens at Kew:
From my experience, I should judge that any study systematically pursued and mast red must necessarily expand the mental powers; but I think I should put classics at the bottom and mathematics next, and I should put na:ural history first, not because it is better than mathematics, but because it can be taught at an age when mathematics would injure the mind, and, further, it is applicable to minds which have no capacity for mathematics. A child can begin natural history at eight or nine years old, and it could be made an amusement and a pleasure if properly taught. A child, after having examined one batter-cup, is enabled thereby to recognize another, though dissimilar, kind of buttercup, and the process affords pleasure.
I know that in conducting the examination of medical men for the army, which I have now conducted for several years, and those for the East India Company's service, which I have conducted for, I think, seven years, the questions which I am in the habit of putting, and which are not answered by the majority of the candidates, are what would have been answered by the children in Professor Henslow's village school. I believe the chief reason to be, that their observing faculties as children have never been trained, such faculties having lain dormant with those who naturally possessed them in a high degree, and having never been developed by training in those who possessed them in a low degree. Furthermore, in most medical schools the whole sum and substance of botanical science is crammed into a four weeks of lectures, and the men leave the class without an accurate knowledge of the merest elements of the science.
The advantage of botany is that you can teach it anywhere and everywhere. The child as he walks along can make use of his botanical knowledge, can preserve his specimen, and, having put his information into writing, can preserve this alongside of the specimen itself. This cannot be done to such advantage by a child in the case of geology, nor any branch of science except natural history ones, of which the most facile for the purpose is botany:
This science cannot be taught properly, or at least exclusively, by lectures. The learner must be accustomed to pull plants to pieces with skill and judgment. Now plants are always accessible, every child has the skill, and judgment
comes by experience and teaching. This is why I so strongly advocate botany as the readiest, simplest, and most practical means for training the observing and reasoning faculties. Such training cannot be given by lectures.
NATURAL HISTORY.-STUDY OF ZOOLOGY.
Prof. T. H. HUXLEY, in a Lecture before the Science Classes at the South Kensington Museum, remarks:
Natural History is the name familiarly applied to the study of the properties of such natural bodies as minerals, plants, and animals; the sciences which embody the knowledge man has acquired upon these subjects are commonly, termed Natural Sciences, in contradistinction to other, so called “physical, sciences; and those who devote themselves especially to the pursuit of such sciences have been, and are, commonly termed * Naturalists."
Linnæns was a naturalist in this wide sense, and his “ Systema Naturæ " was a work upon natural history, in the broadest acceptation of the term; in it, that great methodizing spirit embodied all that was known in his time of the distinctive characters of minerals, animals, and plants. But the enor.nous stimulus which Linnæus gave to the investigation of nature soon rendered it impossible that any one man should write another “Systema Naturæ,” and extremely difficult for any one to become a naturalist such as Linnæus was.
Great as have been the advances made by all the three branches of science, of old included under the title of natural history, there can be no doubt that zoölogy and botany have grown in an enormously greater ratio than mineralogy; and hence, as I suppose, the name of “natural history" has gradually become more and more definitely attached to these prominent divisions of the subject, and by “naturalist” people have meant more and more distinctly to imply a student of the structure and functions of living beings.
However this may be, it is certain that the advance of knowledge has gradually widened the distance between mineralogy and its old associates, while it has drawn zoology and botany closer together; so that of late years it has been found convenient (and indeed necessary) to associate the sciences which deal with vitality and all its phenomena under the common head of " biology;" and the biologists have come to repudiate any blood-relationship with their fosterbrothers, the mineralogists.
Certain broad laws have a general application throughout both the animal and the vegetable worlds, but the ground common to these kingdoms of nature is not of very wide extent, and the multiplicity of details is so great, that the student of living beings finds himself obliged to devote his attention exclusively either to the one or the other. If he elects to study plants, under any aspect, we know at once what to call him; he is a botanist, and his science is botany. But if the investigation of animal life be his choice, the name generally applied to him will vary, according to the kind of animals he studies, or the particular phenomena of animal life to which he confines his attention. If the study of man is his object he is called an anatomist, or a physiologist, or an ethnologist; but if he dissects animals, or examines into the mode in which their functions are performed, he is a comparative anatomist or comparative physiologist. If he turns his attention to fossil animals, he is a palæontologist. If his mind is more par. ticular y directed to the description, specific discrimination, classification, and distribution of animals, he is termed a zoologist.
For the purposes of the present discourse, however, I shall recognize none of these titles save the last, which I shall employ as the eqụivalent of botanist, and I shall use the term zoology as denoting the whole doctrine of animal life, in contradistinction from botany, which signifies the whole doctrine of vegetable life.
Employed in this sense, zoology, like botany, is divisible into three great but subordinate sciences, morphology, physiology, and distribution, each of which may, to a very great extent, be studied independently of the other.
Zoological morphology is the doctrine of animal form or structure. Anatomy is one of its branches, development is another; while classification is the expression of the relations which different animals bcar to one another, in respect of their anatomy and their development.
Zoological distribution is the study of animals in relation to the terrestrial conditions which obtain now, or have obtained at any previous epoch of the earth's history.
Zoölogical physiology, lastly, is the doctrine of the functions or actions of animals. It regards animal bodies as machines impelled by certain forces, and performing an amount of work, which can be expressed in terms of the ordinary