way, that a discipline of classical culture, or of early literary studies, is by no means essential to the training of an effective popular speaker or lecturer upon the severest topics of science. We say each in his way, for the excellencies of Prof. Tyndall and Prof. Huxley are unlike-Prof. Tyndall being strong in illustration, ornament, and suggestiveness, while Prof. Huxley excels in directness, simplicity, and force.

The specialty of Prof. Tyndall, as is well known, is that department of physics which includes the kindred agents of light, heat, and electricity. Prof. Huxley is eminently a physiologist-both human and comparative. Neither of the two, however, confines himself to the specialties named, especially in their popular lectures and addresses-both being more than usually fond of following out the suggestions of physics and physiology in respect to the nature of the soul, the progress and destiny of man, and the origin and end of the physical universe. In plain English, both these gentlemen are very fond of teaching the public metaphysics and theology after what they please to call the methods and conclusions of physical science. We do not altogether blame them for this. The desire and effort show a generous recognition of other phenomena than those which are included within their own departments, and the rooted conviction that all truth is one, and therefore it is impossible that any science of nature should conflict with the other forms of scientific truth, or offend any rational conviction. Prof. Tyndall has appropriated to himself a somewhat wider field of discussion than Prof. Huxley, having discussed very frequently the method of scientific inquiry with a sagacious appreciation of the problem, and with commendable, if not always consistent, sagacity in solving it. From the metaphysics of induction, he has very naturally proceeded to discuss the nature and essence of the soul, and has consequently yielded to the further impulse to inquire what science teaches concerning freedom, morality, immortality, prayer, and God. All this has been done under the impulse of an implicit faith in what he calls science. His confidence concerning his mastery of what he calls the known and the analogies which it suggests in respect to the unknown—his predictions of what is the inevitable tendency of modern thinking in respect to every one of the topics named, and the eager haste with which he seeks to place himself among the foremost of its heralds-are contagiously exhilarating even to the looker-on who neither accepts his data nor his inferences. How much more must the lecturer himself enjoy the glowing excitement with which he sweeps along his triumphant course and the responsive enthusiasm of his confiding and admiring

audiences. It is not surprising, as from year to year he grows. more confident in his psychological and theological faith, and is more and more aware of the power which he wields, that he should take occasion as often as once a year to announce with befitting eloquence and ardour the advances by which the thoughtful men of the age are fast proceeding towards the mastery of the universe by scientific thought after truly scientific methods. On the 1st of October last he gave one of these confessions of his faith before the Birmingham and Midland Institute, of which he is President. It was characterized by his usual gracefulness in the introduction, and by his neverfailing ingenuity in the development, and by more than usually startling frankness in the conclusion. In reading such a discourse we very naturally ask, of what topic does it treat? We confess that this is a question which it is not easy to answer. It might almost seem at first that it treats de omni scibili et quibusdam aliis, so wide is the range of subjects which it passes in review. It will be safe to say in the author's own words that he begins by asserting "that it is now generally admitted that the man of to-day is the child and product of incalculable antecedent time. His physical and intellectual textures have been woven for him during his passage through phases of history and forms of existence which lead the mind back to an abyssmal past," and that he concludes with the equally confident assertions: "Thus following the lead of physical science we are brought without solution of continuity into the presence of problems which as usually classified lie entirely outside the domain of physics. To these problems thoughtful and penetrative minds are now applying those methods of research which in physical science have proved their truth by their fruits. There is on all hands a growing repugnance to invoke the supernatural in accounting for the phenomena of human life; and the thoughtful minds, just referred to, finding no trace of any other origin, are driven to seek in the interaction of social forces the genesis and development of man's moral nature. If they succeed in their search -and I think they are sure to succeed-social duty will be raised to a higher level of significance, and the deepening sense of social duty will, it is to be hoped, lessen, if not obliterate, the strife and heart-burnings which now beset and disfigure our social life." The terminus a quo is evolution as an admitted fact of the widest conceivable application. The terminus ad quem is a rounded scientific theory which excludes all faith in the supernatural and any possible scientific occasion for God; involving as a corollary, the development from society of all the relations and sanctions of moral obligation. This

faith is fitted to elevate practical morality and to deliver social life for ever from its strifes and hatreds. All these positions except one had been asserted or implied in Prof. Tyndall's previous deliverances. The only advanced position which he takes in this discourse is the very familiar dogma of Hobbes, which has been transfigured by Herbert Spencer, that moral distinctions are created or evolved from social relations and are sanctioned by social forces. "But if this is all that is new in this address, why notice it at all? We have had enough of all this at Belfast and on other occasions, and the staple of such reasoning has been so often used that it is becoming somewhat threadbare." But this does not follow. Prof. Tyndall never repeats himself. If his logic is in principle unchanged, the form in which it is presented always varies. Every time he rises to argue on these extra-physical themes, he adduces what he considers new facts, and employs fresh and novel illustrations. He invariably aims to strengthen the most familiar and oftenest. used chain of argument by some links freshly forged. Moreover, he is sensitively alive to what the men of these times are thinking of; so sensitively, that he cannot rest content with old arguments, if new ones are required. He is too ingenuous not to confess, or at least not to betray, his sense of the weakness of some of the positions which he had previously taken, and too ingenious not to attempt to strengthen them. The occasional discourses of so sensitive and frank a thinker as he, are also in a sort the outspeaking of what is going on in the minds of scores and hundreds of men who want the honesty or the opportunity to speak their minds as freely as he speaks for them. What is more to the purpose, they declare the secret misgivings and the more than half-formed creed of multitudes of younger men who know not how to answer the reasons of an argument from the conclusions of which they shrink. These are the reasons why we think it worth while to subject this eloquent discourse to a careful examination. We shall do this with the same frankness which our excellent friend, the author, always exhibits, and we hope with equal fidelity to the scientific spirit by which he is animated.

We observe before the argument begins, a little skirmishing, the design of which is not at first view very obvious. In speaking of the dependence of the individual upon the forces of the past, Prof. Tyndall says that Boyle regarded the universe as a machine, but Mr. Carlyle prefers to regard it as a tree, and adds: "A machine may be defined as an organism with life and direction outside, a tree may be defined as an organism with life and direction within." This language seems novel. Can a machine be an organism,-and an organism with

life? Surely the common speech of Prof. Tyndall has made him forget his philosophy. It seems a pity that his German studies did not suggest to him the well-worn definition from Kant, from whom he is somewhat fond of quoting commonplaces-that "an organism is that in which the parts and the whole are respectively means and ends."* How marvellous that this commonplace and yet fundamental conception of physiology should have been so strangely misconceived, through the apparent haste of Prof. Tyndall to give, as he does, in the next sentence, an atheistic turn to his very inadequate conception of what an organism is. "I close with the conception of Carlyle. The order and energy of the universe I hold to be inherent and not imposed from without-the expression of fixed law and not of arbitrary will." In this also, he forgets the patent truth that in the judgment of the great majority of scientific thinkers an organism in its very conception implies intelligence without itself. His confusion of mechanical with organic relations is still more apparent, as he traces the growth of scientific theories from vague anticipations into verificd discoveries and fixed methods, and concludes with the remark, which is least of all true in respect to the science of organized existence, that "the interdependence of our day has become quantitative-expressible by numbersleading, it must be added, directly into that inexorable reign of law which so many gentle people regard with dread."

In one aspect, as we have said, the intent of these preliminary movements is not very obvious, but in another it is clear that they are designed to prepare his hearers for the conclusion to which he directs every position of his subsequent. argument that the universe of matter and spirit, including as he concedes the phenomena of moral conviction and feeling, as also of religious emotion and religious faith, is in every process and manifestation subject to no other than mechanical laws.

Thus far the movements have been preliminary. The author begins the argument proper with a theme very familiar to himself, viz. the correlation of physical forces. He traces the growth of this theory from the first felicitous conjecture

* "Ein organisches Product der Natur ist das in welchem alles Zweck und wechselseitig auch Mittel ist." Kritik der Urtheils-Kraft, § 66. To understand the complete significance of this phraseology, the reader must bear in mind that Kant denies that a work of art, i.c., a machine of any sort, can properly be said to be organic or organized. In this doctrine most scientists would agree with him.

to the demonstrated conclusion. He illustrates it by the relations of heat to mechanical work and their mutual interchange, in examples with which the readers of his other essays and lectures are entirely familiar. He considers next the analogous interchange of decomposition and combustion in the use of the galvanic battery for chemical results-illustrating by several examples the truth that chemical elements, say hydrogen and oxygen, which are united in combustion at one point in the circuit, are liberated in exact equivalents at the other. Having taken two steps in his argument, he essays a third, and suggests that the same process under similar laws may go on in the body of man. Having demonstrated that heat is interchangeable backwards and forwards with mechanical energy in mathematical equivalents, and that combustion involving heat is in like manner interchangeable with chemical decompositions, he abruptly asks: "Is the animal body then to be classed among machines?" The friction wheel or the galvanic battery only distributes force-transferring it from one point to another, and varying its manifestations to the senses-but never creating it. Does the animal body do anything more? "When I lift a weight, or throw a stone, or climb a mountain, or wrestle with my comrade, am I not conscious of actually creating and expending force?" The ingenuity of thus putting his case is altogether admirable. It is as though he had said the question whether the body is or is not a machine must be decided by the question whether it is capable of generating muscular or mechanical energy. The man who asserts that it only transfers force must own that it is a machine— the man who denies that it is a machine must hold that it can of itself generate, i.e., originate, muscular force. The tyro in logic would recognize the possible fallacy which may lie in the major premise of Prof. Tyndall's disjunctive syllogism. Even did he know little about the subject matter, he might at least be wary enough to say: I am not prepared to say that A is either B or C, for it may possibly be either B, C, or C + D. That is, the human body may be something else than either a generator or a transmuter of force-it may perhaps perform other offices than a friction wheel or a galvanic battery. Whether Prof. Tyndall does not himself concede this a little further on, we shall ask in due time. But Prof. Tyndall having shaped his major premise to suit himself, proceeds to discuss the minor premise by asking whether the human body originates, i.e., generates, mechanical force. He answers his own question by an elaborate and varied series of illustrations, all of which are designed to show that mechanical force and heat and chemism (chemical attraction) are related to one another in