circumstances have no adaptation to make life more, though they may tend to alter its distribution; and simple differentiations and integrations do not account for the immense concentration of structure as well as force, the compressed and implicated variety of parts, which is characteristic of the more developed organisms. The general conception, which, as it seems to us, should be applied to the evolution of life, is one which recognises a pressure of the natural forces tending to give rise to the organic state of matter, and a constant resistance under which this process is carried on, leading to a higher tension of the force, and a more involved structure in the forms in which it is exhibited. This view furnishes also a partial justification of the otherwise untenable doctrine of an inherent tendency in life to progress. There is not an inherent tendency; but there is, apart from changing circumstances, an external constraint. This pressure from without, arising from increase of the vital form of force, Mr. Spencer does not expressly note as bearing on evolution; nor does it appear to us that he assigns it even by implication a due place. Without it, the causes he assigns for evolution appear insufficient to bear the weight which rests on them. Adaptations do not alter totals. It is possible that he may design to make more reference to phenomena of this class in the succeeding volume, to which the discussion of individual structure is deferred; but it seems to us that they should find a place in the treatment of the general doctrine of evolution. Nature becoming organic -that being so far the direction of least resistance for her force-we believe is the great element which lies at the root of the whole process; nature becoming organic under limit. And this balance of vital action and limit or control, again, has the most striking illustration in the life of the individual organism; in which the whole nutrition and every function seem to be thus held in check, a special nervous organisation existing for this very end :which organisation itself, may we not say in accordance with Mr. Spencer's own views, is but the specialisation of an universal function in the organic world? But into this point and many others equally full of interest which press upon us, we have not space to enter now. It is with regret we leave so great a topic so scantily treated, and see our task cut off at its commencement; but we hope to resume it at no very distant day. Biol. Stutrition. Chem.-G.. ssecom portion XXVI. ON THE RELATION BETWEEN CHEMICAL (1862.) My attention has been drawn to the question which heads this paper by my having become unwillingly involved in a controversy as to the origination of the view that the motor power in nutrition is chemical decomposition. Dr. Waters, of St. Louis, in America, on the one hand, claims to be the first propounder of this thought, and Dr. Freke, of Dublin, on the other, affirms his priority. Between them I am not competent to decide, though I am of opinion that both claims are practically just; Dr. Waters' statement being full and complete, but later; Dr. Freke's being earlier, but more indistinct, and perhaps capable of more than one interpretation.1 Dr. Freke says, "We find the living atom has imparted its organic properties to the inorganic matter, and in parting therewith has itself become inorganic." Dr. Waters, and others after him, trace out in express dynamic terms the process as they apprehend it; namely, that in the decay of one portion of organic matter force is set free, which acts as the "organising" force of other matter, either causing it to become organic (having previously not been so), or raising it from a lower to a higher vital 1 "On the Origin of Species by means of Organic Affinity." By H. Freke, M.D., &c. London: Longmans. 1861. P. 48. state. It is in respect to the true that I wish to say a few words. order of ideas here Which is the true thought: Does the first organic matter "impart its force," and thereupon decay? Or does it undergo decay, as representing a "tendency" of the elements, and so come to impart its force? There is no doubt that, with our accustomed ideas of the properties of matter, the latter is the view into which we most readily fall. But on reflection it by no means appears clear that it is the true one. Granting an "inherent chemical affinity," leading, e.g., oxygen and hydrogen to combine into water, there would be a certain natural order in beginning with it. But this conception is one which science now repudiates. The tendency of oxygen to combine with hydrogen is not an inherent property, it is determined by antecedents, and depends on relations apart from those elements. Decomposition, we know, will not take place except under certain conditions. Now, when vitalisation of another portion of matter ensues upon such decomposition, may not the possibility of this vitalisation be precisely the condition which allows or determines the decomposition? Let me take what I consider an analogous case. In a heated body, let me suppose (I think it is in such sense true as to serve the purpose of the illustration) there is a tendency of the particles, which the heat has separated, to approximate to one another, i.e., a tendency of the body to contract (on cooling). But this contraction cannot take place if the heat cannot be radiated. The condition. for the contraction is that there shall be some body to which the expansion-producing (or the contraction-controlling) principle (the heat) can be passed on-some cooler body, in a word, within a certain distance. As the one body expands the other contracts; but which comes first, the contraction of the cooling body, or the radiation— the transit of the heat? To me it seems that this question goes deep into the most recondite questions of molecular physics; but in the representation of vital action as "produced by" decay, is it not quietly assumed that the cooling, or contraction, stands as cause? I grant that when we take parallels of another sort, as, e.g., a clock moved by weights, the order seems simple enough. The hands move, &c., because the weights fall, and the weights fall because of their gravity, and so on. But we must remember there is no gravity except as a result of conditions. Will the weights fall if the hands cannot move? Or take the simpler case of the balance. Suppose it in equilibrium; two changes will equally set it in motion, increase or diminution of weight in one scale. The raised condition must be imparted-transferredor it cannot cease. It may be said, indeed, sever the connection of the scales, and the one will fall and the other will not rise; but something else will rise, or undergo some change equivalent to rising. The law is not altered, but only its particular application. The fall is seen, while the rising escapes our vision. We must be on our guard here lest the particular character and limitations of our experience deceive us, bringing, as it does, before us so preponderating a number of instances in which the downward process is the prominent one, the upward secret or out of reach. But that the order of our experience must not be relied upon is evident from the fact that it differs in different cases, and in each produces on our minds the same impression, although mutually contradictory, of "natural tendencies," and of the beginning being in reality where it seems to be. So from the inorganic world we derive, from preponderance of instances, the impression that the |