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the logical faculty of investigation is well trained. Nothing so marks the imperfectly educated man as his helplessness when dealing with facts instead of men, and his insecurity both in arriving at truth from them, and in judging of the validity of the conclusions of others. For the advance of thought, on all subjects which require thought, this faculty of investigation is indispensable. Probably no study will cultivate one of these faculties and wholly neglect the others, but all studies aim principally at one or the other of these. A study of the classical languages, for example, is an artistic exercise, and moreover it educates the receptive faculties in a manner in which no other study educates them. The study of a language and literature not our own is the best preparation for entering into the thoughts of others; but even when best taught and best learned it can only be a very imperfect exercise in logic, for it omits nearly the whole of the logic of induction. The study of science, on the other hand, while not without its influence on even the artistic powers, and exercising in a remarkable degree the powers of intelligence of a certain kind, deals mainly with the faculty of investigation, and trains the mind to ponder and reflect on the significance of facts. And the methods of these studies are in many respects precisely the same. Models and exercises are given by the one; models and exercises by the other. Thucydides must be read, and Latin prose must be written, by the student of form and style; and the man who would cultivate his powers of thought must read his Newton, and study Experimental Physics. And as the student of Thucydides and Plato is likely to gain in clearness and brilliance of expression, and an insight into history and humanity, in intelligent and ready apprehension of the thoughts of others, in versatility and in polish; so the student of natural science is likely to bring with him to the study of philosophy, or politics, or business, or his profession, whatever it may be, a more active and original mind, a sounder judgment, and a clearer head, in consequence of his study. A good style perhaps may be got by reading and writing; thinking is learnt by thinking. And therefore that method of giving scientific instruction is best which most stimulates thought; and those subjects which afford the best illustrations of the best method ought to be selected for instruction in schools.

Different Methods of Teaching Science.

Now there are two methods of teaching science: one, the method of investiga tion; the other, the method of authority. The first starts with the concrete and works up to the abstract; starts with facts and ends with laws: begins with the known, and proceeds to the unknown; the second starts with what we call the principles of the science; announces laws and includes the facts under them: declares the unknown and applies it to the known. The first demands faith, the second criticism. Of the two, the latter is the easier, and the former by far the better. But the latter is seen in most text-books, and is the method on which many unscientific people ground their disapproval of science. What this former method is, and why it is the better, will be seen by the following remarks. In the first place, then, knowledge must precede science: for science is nothing else but systematized experience and knowledge. In its extreme applications this principle is obvious enough: it would be absurd to teach boys classification from minerals, or the power of experimental science by an investigation into the organic bases. A certain broad array of facts must pre-exist before scientific

methods can be applied.* This order cannot be reversed. And this is illustrated by the profound analogy that exists between the growth of scientific knowledge in an individual and in the world. Generation after generation of men passed away, and the world patiently accumulated experience and observation of facts; and then there sprang up in the world the uncontrollable desire to ascertain the sequences in nature, and to penetrate to the deep-lying principles of natural philosophy. And the same desire is based in the individual on the same kind of experience. Where there is wide knowledge of facts, science of some kind is sure to spring up. After centuries of experience the Philosophic naturalis principia were published.

And, secondly, this knowledge must be homogeneous with pre-existing knowledge. It is of no use to supply purely foreign facts; they must be such as the learner already knows something of, or be so similar in kind that his knowledge of them is equally secure: such that he can piece them in with his own fragmentary but widening experience. It is to his existing knowledge, and to that alone, that you must dig down to get a sure foundation. And the facts of your science must reach continuously down, and rest securely thereon. Otherwise you will be building a castle in the air. Hence the master's business is to take up the knowledge that already exists; to systematize and arrange it; to give it extension here, and accuracy there; to connect scraps of knowledge that seemed isolated; to point out where progress is stopped by ignoranee of facts; and to show how to remedy the ignorance. Rapidly knowledge crystallizes round a solid nucleus; and anything the master gives that is suited to the existing knowledge is absorbed and assimilated into the growing mass: and if he is unwise and impatient enough (as I have been scores of times) to say something which is to him perhaps a truth most vivid and suggestive, but for which his boys are unripe, he will see them, if they are really well trained, reject it as the cock despised the diamond among the barley (and the cock was quite right), or still worse, less wise than the cock, swallow it whole as a dead and choking formula.

On these grounds then, in addition to other obvious ones, Botany and Experimental Physics claim to be the standard subjects for the scientific teaching at schools. In both there pre-exists some solid and familiar knowledge. Both can so be taught as to make the learner advance from the known to the unknownfrom his observations and experiments to his generalizations and laws, and ascend by continuous steps from induction to induction, and never once feel that he is carried away by a stream of words, and is reasoning about words rather than things. The logical processes they involve are admirable and complete illustrations of universal logic, and yet are not too difficult. These considerations mark the inferiority in this respect, of Geology and Physiology, in which the doctrines must far outrun the facts at a boy's command, and which require so much knowledge before the doctrines can be seen to be well founded. And these considerations exclude Chemistry, as an elementary subject at least, since there is so little pre-existing knowledge in the learner's mind on which the foun

*This truth has been entirely lost sight of in teaching elementary geometry. The extreme repulsiveness of Euclid to almost every boy is a complete proof, if indeed other proofs were wanting, that the ordinary methods of studying geometry in use at preparatory and public schools are wholly erroneous. To this I can do no more than allude here, as being my conviction after considerable experience,-a conviction which has overcome every possible prejudice to the contrary. It is much to be hoped that before long the teaching of practical geometry will precede the teaching of the science of geometry,

dations can be laid. On all grounds the teaching of Chemistry should follow that of Experimental Physics.

Unless this method of investigation is followed, the teaching of science may degenerate, with an amazing rapidity, into cramming. To be crammed is to have words and formulæ given before the ideas and laws are realized. Geology and Chemistry are frightfully crammable. But Botany and Experimental Physics are by no means so easy to cram. What they might become with bad textbooks and a bad teacher, I cannot, indeed, say; but it is a very important consideration. For it is possible to teach even Botany and Experimental Physics with exquisite perverseness, so as to deprive them of all their singular advantages as subjects for elementary training in science. It is possible to compel the learning the names of the parts of a flower before the condition of existence of a name, viz. that it is seen to be wanted, is fulfilled; to cumber the learner with a terminology that is unspeakably repulsive when given too soon; given before the induction which justifies the name has been gone through; to give the principles of classification before a sufficient acquaintance with species has called out the ideas of resemblance and difference, and has shown the necessity of classification; to give theories of typical form when it seems a wild and grotesque romance; to teach, in fact, by the method of authority. And this may be done by truly scientific men, fully believing that this is the true and only method. Witness Adrien Jussieu's "Botanique."

The true method is assuredly to begin by widening for your boys the basis of facts, and instantly to note uniformities of a low order, and let them hazard a few generalizations.

Specimen Lesson in Botany.

Suppose then your class of thirty or forty boys before you, of ages from thirteen to sixteen, as they sit at their first botanical lesson; some curious to know what is going to happen, some resigned to anything; some convinced that it is all a folly. You hand round to each boy several specimens, say of the Herb Robert, and taking one of the flowers, you ask one of them to describe the parts of it. "Some pink leaves" is the reply. "How many?" "Five." "Any other parts?" "Some little things inside." "Anything outside ?" "Some green leaves." "How many?" "Five." "Very good. Now pull off the five green leaves outside, and lay them side by side; next pull off the five pink leaves, and lay them side by side: and now examine the little things inside. What do you find? "A lot of little stalks or things." "Pull them off and count them :" they find ten. Then show them the little dust-bags at the top, and finally the curiously constructed central column, and the carefully concealed seeds. By this time all are on the alert. Then we resume: the parts in that flower are, outer green envelope, inner colored envelope, the little stalks with dust bags, and the central column with the seeds. Then you give them all wall flowers and they are to write down what they find: and you go round and see what they write down. Probably some one has found six "storks" inside his wall flower, and you make him write on the black-board for the benefit of the class the curious discovery, charging them all to note any such accidental varieties in future; and you make them very minutely notice all the structure of the central column. Then you give them all the common pelargonium and treat it similarly; and by the end of the hour they have learnt one great lesson, the existence of the four floral whorls, though they have yet not heard the name.

Next lesson-time they come in looking more in earnest, and you give them single stocks and white alyssum, which they discover to be wonderfully like the wall flower; and you have a lot of flowers of vegetable marrow, some of which are being passed round while you draw two of them on the board. The difference is soon discovered; and you let them guess about the uses of the parts of the flower. The green outer leaves protect it in the bud; the central organ is for the seeds; but what is the use of the others. Then you relate stories of how it was found out what the use of the dust-bags is: how patient Germans lay in the sun all day to wait for the insects coming: and how the existence of a second rare specimen of some foreign tree was found out in Paris, by its long-widowed spouse in the Jardin des Plantes at last producing perfect seeds. A little talk about bees, and moths, and midges, and such creatures, finding out what they have seen, and your second lecture is over.

In the third lecture you take the garden geranium, and beg them to examine it very closely to see if it is symmetrical. Several will discover the unsymmetrical outer green leaves; one or two will discover the hollow back of the stem: then the pelargonium, and its more visible unsymmetry; then the common tropæolum in each of which they find also the same parts, and count and describe them and lastly the tropæolum Canariense, with its grotesque irregularity and they are startled to find that the curious-looking flower they knew so well is constructed on the same type, and is called by the same name; and by the end of the lesson they have learned something of irregular flowers, as referred to regular types,-something of continuity in nature.

So in succession, for I cannot give more detail, you lead them through flowers where the parts cohere, as in the campanula, through plants deficient or odd, through roses, and mignonette, and honeysuckle, and all the simple flowers you can find; till they thoroughly know the scheme on which a simple flower is made. Then you challenge them to a dandelion or daisy: and each has to write down his ideas. Your one or two geniuses will hit it: some will be all wrong, without a shadow of doubt; the majority fairly puzzled. You give them no hint of the solution, tell them to lay it aside; and you give them the little thrift and challenge them to find its seeds, and how they are attached. This many will do, and pick out the little seed with its long thread of attachment, and then they will go back to their dandelions with the key to the structure; and find its seeds too, and be charmed to discover the remains of its poor outer green envelope, and even its little dust-bags. How proud they are of the discovery! they think they have the key of knowledge now. And then you begin a little terminology, calyx and sepals, corolla and petals, stamens and pollen, pistil and stigma, and so on; and test their recollection of the forms of all the flowers they have examined. Then you notice the spiral arrangement of leaves on a twig of oak, or thorn, or willow, and the internodes; and the over-lapping of the sepals of the rose and Herb Robert; the alternance of the parts; and finally they work out the idea, that the floral whorls grow on the stem, and are a sort of depressed spiral of leaves with the internodes suppressed. A few monstrosities and pictures are shewn, and the grand generalization is made; the pistils are re-examined with fresh interest to test the theory; and all their old knowledge is raked up once more. Then, too, the value of the theory is criticised; and a lesson of caution is learnt.

Then a step forward is made towards classification, by cohesion and adhesion of parts; and the floral schedule is worked; and so step by step to fruits, and

leaves, and stems, and roots, and the wondrous modification of parts for special uses, as in climbing plants; and the orchids, which are a grand puzzle till a series of pictures from Darwin step in to explain the use of the parts and plan of the flower. Then some chemistry of the plant is introduced with some exper iments, and the functions of all the organs are discussed. And lastly, strict descriptive terms are given, and the rest of the course is occupied by the history and the systems of classification, with constant reference however to the other conceptions that the class has gained.

Such a method as this has many advantages. It is thoroughly scientific, how. ever irregular it may seem, and a professor of Botany may smile or shed tears over it for anything I care; and the knowledge is gained on a sound basis of original observation. Whatever flower a boy secs after a few lessons, he looks at with interest, as modifying the view of flowers he has attained to. He is tempted by his discoveries: he is on the verge of the unknown, and perpetually transferring to the known: all that he sees finds a place in his theories, and in turn reacts upon them, for his theories are growing. He is fairly committed to the struggle in the vast field of observation, and he learns that the test of a theory is its power of including facts. He learns that he must use his eyes, and his reason, and that then he is equipped with all that is necessary for discovering truth. He learns that he is capable of judging of other people's views, and of forming an opinion of his own. He learns that nothing in the plant, however minute, is unimportant; that he must observe truthfully and carefully; that he owes only temporary allegiance to the doctrines of his master, and not a perpetual faith. No wonder that Botany, so taught, is interesting no wonder that M. Demogeot, who visited some English schools last year at the request of the French Emperor, expressed himself to me as charmed with the vivacity and intelligence of the botanical class of one of my colleagues.*

Very possibly a master might make his boys get up a book on Botany, and learn it in the order in which it stands in the book,-cellules and parenchyme, protoplasm and chlorophyll, stems and medullary rays, petioles and phyllodes, rhizomes and bulbs, hairs and glands, endosmose and exosmose, secretions and excretions, and so on, and so on; and ultimately come to the flower and fruit; and possibly a boy of good digestion might survive it and pass a respectable exam. ination in a year's time. But this is not the aim. And if in this way a greater number of facts could be learned, it would be far inferior to the method of investigation. A master must never forget that his power of teaching facts and principles is far inferior to a willing pupil's power of learning and mastering them. He must inspire his boys, and rely on them: nor will he be disappointed. Those who have in them anything of the naturalist will collect and become acquainted with a large number of species, and follow out the study with care and accuracy; and the mass, to whom an extensive knowledge of species is a very unimportant matter, but who can appreciate a sound method of investigation and proof, will have gained all that they can gain from botanical teaching. And it must be remembered by those who speak of teaching science, and yet have never tried it, that a method which would succeed with a few naturalists, might utterly fail with the mass.

*The spirit of this method is admirably illustrated in Le Maoût's "Leçons élémentaries de Botanique, fordées sur l'Analyse de 50 Plantes vulgaires."

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