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day's debate, is the fact that it has at last dawned upon the leaders of opinion and the makers of our laws that “education” and “instruction are different things, and that a man may learn a great many “ facts” at school, and have his education to begin when he leaves it. It is lamentable that we have to be continually reminded that we are the only one of the great European countries where this distinction is not recognized and practically carried out in education. Our whole system of education, hitherto, has been a mere cramming of the children's memories with words, words, words, to the weariness of children and teachers, and with results unsatisfactory to all concerned. As the Times puts it, “To be taught something about gravitation, about atmospheric pressure, about the effects of temperature, and other simple matters of like kind, which would admit of experimental illustration, and which would call upon the learner to make statements in his own words instead of in those of somebody else, would be so many steps toward real mental development." Sir John Lubbock gave a most conclusive refutation of the idea that the teaching of science must be attended with hitherto unexperienced difficulties, and at the same time proved what a relief science-teaching would be to the ordinary dull routine of instruction, when he told the House that in the Scotch schools the authorities began to take alarm because science-teaching was found so comparatively easy and pleasant by the children. the argument that children who have been taught to know something about the object and forces with which they come every day into contact contract a distaste for manual labor, we should have thought it had been long ago played out; it has almost as much force as the story told by another speaker of the boy who had been impudent to his master because the latter could not read his newspaper.

It is unnecessary for us to go again into the merits of the question which has been so often and so thoroughly discussed in these pages, especially as the Times has put it quite as forcibly as there is occasion for doing at present. It certainly seems sad, nationally suicidal, indeed, that a few more millions of those who will have the destinies of this country in their hands are likely to be launched into active life, with all their education to acquire, ere legislation steps in to give us the advantages which nearly every other civilized nation gives to its children. Every day we hear of the ignorance of the working-classes, every other

congresses are held to devise means to remedy the consequences of this ignorance-ignorance of the laws of health, ignorance of household economy, ignorance of the implements and objects of labor, ignorance of the laws of labor and production, ignorance of the nature of the commonest objects with which they come into contact every day, ignorance of almost everything which it would be useful and nationally beneficial for them to know—an ignorance, alas! more or less shared by the “curled darlings” of the nation. Yet while every day's paper shows how keen is the industrial competition with other nations, and how in one department after another we are being outstripped by the results of better-i. e., more scientific—knowledge, the poor pittance of "elementary knowledge" asked for in Sir John Lubbock's bill is refused by a minister whose own “education” leaves much to be desired. This state of things cannot long continue, and with such advocates for the children as the Times and Mr. Forster, we may hope that next time Sir John Lubbock brings forward his bill it will meet with a happier fate.- Nature.

month 66




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LET us suppose that we have before us a living spherule of the uni

form viscid material of so-called protoplasm. It is seen slowly to push forth, at some part of its circumference, a conical process; and, after a while, it is seen still more slowly to retract the same. here brought face to face with the initial and fundamental manifestation of one of the chief properties of life. For, what we are observing is living motion, incipient motility. How is it accomplished ? What changes in the protoplasm have given rise to this duplex movement, first of protrusion, and then of recoil, on the part of a peculiar portion of the living material ?

When the phenomenon is closely watched in different kinds of monera, it becomes evident that the conical projections are formed by a portion of the protoplasm, in which the bonds of cohesion are in some way being loosened; for the matter flows out into space with a certain pushing force--it liquefies and expands. This view is quickly corroborated by the unmistakable recontraction and resolidification of the material forming the projections, when retrogression is taking place. It is plain, then, that alternate expansion and contraction are the visible elements of motility.

Strange to say, biologists have as yet only realized the importance of the latter, less fundamental part of this twofold process. They have been so struck with the peculiar contractile power,

with the seemingly sensitive shrinking exhibited by the living substance, that they have deemed it the most salient and characteristic manifestation of life. To convey this notion, they generally give to the protoplasm the name of contractile substance.

Now, “contractility” may be a very expressive term for the property by which the protoplasm is enabled to accomplish the second part, the retrograde half of motility ; but, even thus restricted, it in

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cludes too much vitalism to suit our present purpose, which is to link the organic to the inorganic world.

We, therefore, cannot allow our scientific inquisitiveness to be arrested by the interposition of a mere name, or qualitas occulta. We do not wish to make known to others that contraction actually occurs in the living substance, for that is notorious. We wish to ascertain for ourselves how this contraction is effected—whether it is the work of entirely new forces exclusively appertaining to life, or whether it is the mechanical expression of molecular forces, with which we are already familiar in the domain of inorganic activities. Is it a specifically vital force which executes the contraction of motility ? Or is it a molecular activity of a known kind which gives rise to vital motion ?

This simple question may appear to some very unexciting; yet, upon its answer turns, nevertheless, the entire problem of life ; for it is just at this point that the doom of vitalism has to be sealed. Vitalism or evolution : these two conceptions of Nature are incompatible. Vitalism means essentially the era of metaphysical agencies, the sway of extraneous powers coercing a resisting world of stubborn matter. Evolution means the era of inherent efficiency, the interaction of intrinsic powers ever elevating the constant realm of transient existences. It is of great importance, then, not to be deceived with regard to the exact manner in which this decisive vital act, the contraction of motility, is at all times being performed in Nature.

Fortunately, our monera give us plain information upon this point. It can be proved that it is chemical decomposition by which the liquefied and expanded material of the conical projection is caused to assume its former condition and place in space. The living substance contracts because it suffers decomposition, as can be directly witnessed. On the strength of this observation it would be quite legitimate to infer that it must have been chemical composition which also caused the reverse activity-which made a portion of the protoplasm start out from its globular limitation, and form a projection measuring in length in some cases more than three times the diameter of the main body. But we are not reduced to mere inference in this instance, so important to the understanding of vitality. By means of various accompanying appearances we can visibly ascertain that it is really a process of chemical composition which underlies the liquefaction and expansion of motility. This leading property of vitality is brought into actual play by the expansion of a certain substance in course of composition, and by the contraction of the same substance in course of decomposition, expansion and contraction being merely the physical concomitants of a definite chemical occurrence. This is shown on the one hand by the products of decomposition being separated and eliminated under our view, and on the other hand by the combining substances being brought together, and effecting their union during inspection. We have no occasion, then, to appeal to the intervention of any specific force in

order to understand motility ; that is, to understand it in the same manner as we understand other natural processes not belonging to vitality. We have here evidently only a display of specific chemistry. But, then, chemistry is specific all through down to H,O, CO,, and NH,, and who knows how much ther?

Expansion and contraction are, as is well known, no uncommon physical concomitants of mere chemical activity, even without addition or subtraction of masses ; and it is of fundamental importance clearly to comprehend that vital expansion and contraction are of the same chemical kind, being due to the intrinsic nature of the compound, not to the mere addition or subtraction of mass.

A part of the protoplasm of a moner expands. Chemical composition of a specific kind has taken place, and now it is the physical property of this peculiar compound to occupy more space than before; then the same part of the moner contracts in consequence of chemical decomposition. It is the physical property of the less complicated organic molecule to occupy so much less space. The mass of the added or separated material fills but a very small part of the entire space of expansion or contraction. The expansion as well as the contraction forms part of the specific nature of those different kinds of protoplasm. The organic substance of the moner, plus the separating molecule, is the expanded material. The organic substance of the moner, minus the separating molecule, is the contracted material. The activities of expansion and contraction are merely the physical expression of the gradual process of composition or decomposition occurring within the living substance; they are marks of the shifting of the special relation existing between the protoplasm and its medium during the transitional stages from one state of equilibrium to another.

The great truth which I wish to make quite evident is, that the specific nature of the acting substance constitutes the real power in motility, and not, as is usually believed, the addition of something from outside.

Vital processes will never become intelligible until it is clearly perceived that all vital efficacy resides in the living substance itself, forms an integral part of its specific nature. Many serious misconceptions are afloat with regard to the source of vital power. Science has as yet scarcely penetrated into the outermost precincts of the laboratory of life. The so-called vital dynamics of the present day are beggarly conceptions when measured against the actual wealth of vital manifestations. All we know is, that if so much pressure, so much heat, etc., will effect a new molecular equilibrium in a certain substance, that substance will return to the medium what it has received from it in reassuming its former state.

Will any one pretend to compute the value of the influences which the living substance in the course of ages has absorbed from its medium, in order to become what it at present is? Yet it is these assimi


lated, equilibrated influences which constitute its real wealth, its source of power, its store of potential energy, whence all its performances emanate.

In the execution of vital motion matter is to some extent sumed.” During expansion it is consumed—taken up by the expanding substance at the cost of the medium. During contraction it is consumed-taken up by the medium at the cost of the contracting substance.

Now, in conformity with the prevailing one-sided view of motility, which attributes the entire phenomenon to so-called contractility, it is generally supposed that the force displayed during living motion is derived exclusively from the consumption of matter on the part of the medium ; and it is also generally supposed that this consumption consists in a process of oxidation. Oxidation, it is said, generates a certain amount of heat; this heat is the real motor power in the case.

It does not much affect the bearings of this view whether the oxidizing material be derived, as some maintain, from the contracting substance itself, or whether, as others think, it be derived from foodingredients. The combustion of matter, with accompanying evolution of heat, is deemed to be the true source of power; and the contracting substance—the muscular fibres in higher animals—are stated to be playing merely the part of machinery.

Thus viewed, the problem of life may be considered altogether hopeless. The organism then represents nothing but a force-directing engine, in which the combustion of compounds previously put together in vegetables constitutes the actual driving force. Vital manifestations, accordingly, can be only due to the action of the force liberated from vegetable compounds and applied to the organic machinery. Poor Science, of all-powerful vitality, thou art very young yet, and amazingly unconscious withal !

The moving substance, the protoplasm, plays just so much or just so little the part of machinery as the steam does in the steam-engine. The substance H,O in a calorific medium from about 32° to 212° Fahr., under ordinary atmospheric pressure, occupies a certain space. In a calorific medium abore 212°, under the same pressure, it occupies an enormously larger space. This specific property of filling such different spaces, under these different thermal conditions, is the very source of its power—of that motor power which sets the engine going. Whoever wishes to become fully convinced of the fact that it is not the heat of combustion, but the specific expansibility and contractility of H, O, by which the engine is driven, may just throw, instead of so much H,O, a proportionate weight of Au into the boiler.

If this remark should happen to appear far too commonplace for the

purposes of scientific illustration, I can merely state in defense of it that, perhaps, in pondering over its meaning, the reader will find himself initiated into a deeper view of force than is usually accepted.

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