Evolution And the Origin of Life.

By Sir Robert Stout, K.C.M.G.

It is said that in every new country the first efforts of the colonists must be applied to the preservation of their lives; houses or shelter of some kind must be provided, food must be got, and, to find food, the land has to be tilled or made suitable for the growth of life, whether plant or animal. Then clothing must be supplied, and that must be obtained at first from countries where manufacturers exist, and something found, or created, in the new country that can he exchanged with merchants, or manufacturers, for the goods that must be imported.' This must be the first or initial stage of the colonist's life. Soon he has to set about making provision for other things. The youths have to be educated, and education cannot stop at what are termed the three R's. Man is an intellectual being, and as the colony gets older, and develops, there must be the discussion of the highest philosophy, and of those things that furnish food for thought amongst the most intellectual of our race. The problems of life will transcend many of the questions on which we have had much discussion. The Hawke's Bay Philosophical Society has, also, its practical side. Questions that are of interest to food suppliers, to those who take an interest in social life, to those also who have to supply the necessities of existence are not foreign to your society. There are, however, questions that should especially come within its ken. One is the origin of things. That and questions related to it may be separated from a discussion of those subjects that lie in what has been termed the religious sphere. Professor A. E. Taylor, of St. Andrews, in his book on Metaphysics, says: "Specifically religious emotion, as we can detect it both in our own experience, if we happen to possess the religious temperament, and in the devotional literature of the world, appears to be essentially a mingled condition of exaltation and humility arising from an immediate sense of communion and co-operation that a power greater and better than ours, in which our ideas of good page 2 find completer realisation than they ever obtain in the empirically known time-order."

Now this sphere we need not enter, in any Philosophical Society. We can deal with the origin of things and try and find out all we can about existence, and how it came about without crossing into the sphere of religion. If, unhappily, in some religious books there should be statements not verified, or not verifiable, or even opposed to our observation and experience, we must pass them by, and not cease to strive to find out the exact truth about all that is in the universe. No question of this kind can be settled by a general vote of any community. A referendum on the question of the origin of life we all, I am sure, realise would be a farcical proceeding; if even a referendum on any question touching the higher issues of life or even human wellbeing is ever a wise proceeding. Viscount Morley, in his most recent book, calls "Plebescites, referenda, and the rest, pieces of supererogation calculated to shred away the constitutional voice of a governing representative assembly." He was no doubt discussing the question from the political standpoint. Mankind must think of these higher issues of life, and not be swayed by the opinions of their ancestors, if they are not verifiable, or if they should happen to be proved to be wrong. The one thing necessary for the race is thought, more thought, and always thought. Let us spend an hour in seeing what science has to tell us of the problems of existence.

We have one word now in common use that before 1859 was not often heard in our midst I mean the word "Evolution." There were theories of the development of men and things before Darwin's work "The Origin of Species," but firmly fixed in the popular belief was the story of creation told us in ancient Babylonian and Hebrew literature. It was believed that there had been what was called "special creation." The great botanist Linnaeus thus explained it: "There are as many different kinds of species as the Infinite Being has created different forms in the beginning. These forms have later engendered other beings according to the law of inheritance, always resembling them so that we have at the present time not any more species than there were from the beginning." Trees, plants, animals, man—all were created as special beings or things. Birds did not develope from reptiles, nor man from an animal unlike man of to day. The oak tree was specially created; the horse did not come from a small animal with four toes in front and three toes behind, called now the Eohippus, or perhaps from the Hyracotherium, a coneylike creature. The Eohippus, we are told, was not more than eleven inches high, and it is said it had an ancestor, Phenacodus, with five toes. Professors Thomson and Geddes say, in their hook on Evolution that "Although we are not even now able to state the lineage of the modern horse, the chief steps in the evolutionary process stand out with clearness, and he must be dull indeed who can see the admirably arranged and convincing series in the museums at Yale and New York without a thrill of admiration, at the wonderful reconstruction of the ancient history of the noblest race of animals, and that most widely identified with man." There is now-a-days no zoologist of standing but admits that birds came from reptiles, and Professor Thomson tells us, that in our lifetime the creations of what would have been termed, if we had found them wild, ten distinct genera of pigeons all created by man's action of breeding have been produced. Evolution is admitted, and that means that all the present life both animal and vegetable, on the globe has come from prior forms, and the ancestors of the present forms would not be recognisable as ancesters were we to see them to-day. The evolution has been so gradual, and so long continued, that the difference between the far back ancestor, and the present representative is exceedingly great. Some connecting links have been found. If any of us have ever visited the British Museum we would have seen no doubt the fossil remains of the half reptile and half bird called the Archaeopteryx, which was a creature about the size of a small gull with bird's feathers and bird's legs, and bird's skull, but with reptile teeth, and the long lizard-like tail and three claws on its undeveloped wing; and it is said that this animal is an ancestor of our present birds. Nor has this change happened merely in reference to animals such as birds or what we might term wild animals. This change has happened in the development of man, and the recent discovery in Sussex of the skull of a river-gravel man is further evidence that the ancestor of man was very unlike the man of to-day. No distinguished man of science rejects the principle of Evolution. The records of the earth are sufficient, however defec- page 3 tive they may be, to prove that animals and plants have developed, and I might illustrate this from what the records of the earth show has happened, in regard to vegetable life. We have flowering plants. The name used by botanists for flowering plants is angiosperms (angiosperms mean "seeds enclosed"; gynmosperms means seed naked or exposed), and it is supposed that we have now in the world 103,000 kinds of flowering plants; of gymnosperms, 2500; of vascular cryptogams (e.g., ferns), 3500; of mosses and liverworts, 7500; of fungi and bacteria, 40,000; of lichens, 5500; and of algae (e.g., seaweeds), 14,000 making altogether 176,000 of different kinds of plant and vegetable life. It will be noticed that the flowering plants number about four-sevenths of all. Now at one time there were no flowering plants in the world. The first record we have of flowering plants appears in what is called the Cretaceous epoch, and that, as compared with the age of the world, is a recent development. There are in geological classification no less than eight older epochs, and immediately after the Cretaceous comes what is termed the Tertiary. In older formations there are found fossil plants, fossil "birds, etc., and fossil reptiles, but the flowering plants were a late development. We now have flowers covering the world. Even in the highest altitudes flowers are found—on mountains over 14,000 feet in height—flowers are also found in tropical parts, and yet at one time there were no flowers. Before the flowering plants there were pines, ginkgoles, or maiden-hair trees, and cycads. Some of those ancient trees still subsist with us; we have pines and gingkpoles. You can see the ginkgol, which is now the sacred tree of the Buddhist, growing in the Government grounds, Wellington, and I have seen two of them in the gardens at Hanmer, while no doubt a few are found in other places in New Zealand, having been imported to the Dominion, They are natives of China and Japan. If you read Dr. Scott's little book on "The Evolution of Plants" published in the Home University Library series, you will see how the flowering plants arose from these gymnosperms. It took a long while before plants had either flowers or seeds, and without the aid of insects it would have been impossible for some plants to have either flowers or seeds.

One distinguished Palaeontologist has said that "Just in proportion to the completeness of the record is the unequivocal character of its testimony to the truth of the evolutionary theory," And were it necessary I could refer to Haeckel's evidence from prenatal life, which reveals the evolution even of man. Goethe, before biological science had made any great advance, pointed out the resemblance in the structures of most animals, and Darwin gave illustrations of the striking fact that many had the same pattern in their ancestry.

How inexplicable is the similar pattern of the hand of a man, the loot of a dog, the wing of a bat, the flipper of a seal in the doctrine of independent acts of creation? But how simply explained is this similarity on the principal of natural selection, of successive slight variations in the diverging descendants, from a single progenitor. Owen had pointed out how many structures are homologous—that is, like each other, such as the wing of a bird, the arm of a man, being both fore limbs with similar muscles, and nerves and blood-vessels. Then we have some structures that are like but not similar, analogous but not homologous, such as the wing of a bird, and the wing of a butterfly, and we have some structures both like and similar, such as the wing of a bird, and the wing of a bat. If you have homologous structures, evolution or development is at all events suggested. It would take, however, much time were I to recite to you the many proofs of evolution.

How the evolution has come about is not, however, agreed upon. Professor G. H. Darwin, in his address as President of the British Association in 1905, spoke as follows about the different theories of evolution:—"We may liken the facts on which theories of evolution are based to a confused heap of beads, from which a keen-sighted searcher after truth picks out and strings together a few which happen to catch his eye as possessing certain resemblances. Until recently, theories of evolution in both realms of Nature were partial and discontinuous, and the chains of facts were correspondingly short and disconnected. At length the theory of Natural Selection, by formulating the cause of the divergence of forms in the organic world from the parental stock, furnished the naturalist with a clue by which he examined the disordered mass of facts before him, and he was thus enabled to go far in deducing order where chaos had ruled before, but the problem of reducing the heap to perfect order will probably baffle the ingenuity of the investigator for ever. So illuminating has been this new idea that, as the whole of Nature has gradually page 4 been re-examined by its aid, thousands of new facts have been brought to light, and have been strung in due order on the necklace of knowledge. Indeed, the transformation resulting from the new point of view has been so far-reaching as almost to justify the misapprehension of the unscientific as to the date when the doctrines of evolution first originated in the mind of man. It is not my object, nor indeed am I competent, to examine the extent to which the Theory of Natural Selection has needed modification since it was first formulated by my father and Wallace. But I am surely justified in maintaining that the general principle holds its place firmly as a permanent acquisition to modes of thought."

There are many who still accept Charles Darwin's Theory of Natural Selection. I should say the majority of the biologists at the Cambridge Darwin Centenary did so accept it, but it is not the only theory, and one of Darwin's theories of Pangenesis is not accepted by many. Weissmann's theory is that there is germplasm continuous in the race, that passes on from mother to daughter, and is not reproduced fresh in each. He says that this germplasm is not modified by surroundings, save by blood infection or a vague penetrative inficiente like heat or cold in small organisms (see McCabe on "Evolution'), and that therefore modifications in structure, etc., are not transmitted. Does, it has been asked, the strong arm—from use—of the blacksmith descend to his offspring? Herbert Spencer disagreed with Weismann. Professor Thomson of Aberdeen, and Professor Geddes put the matter thus:—"Yet another consideration. Although we do not know of any case of the transmission of a modification as such, or even in a representative degree, we, of course, agree with Weismann in admitting that modifications may have secondary effects on the germcells, and thus on the offspring. In this way 'nurture' may come to have a racial importance. Nor can we forget that the environment of mammalian mothers is bound to have an influence on the unborn young, which shares the maternal life so closely. Apart from the 'mysterious wireless telegraphy of antenatal life,' there is a sharing of the diffusible substances carried by the blood."

They quote what may be a bridge to connect the Darwinians with those called the neo-Darwinians: "The interesting suggestion has been made, independently by Mark Baldwin, Lloyd Morgan and Osborn, that useful 'modifications' may serve as the fostering nurses of 'variations' in the same direction: 'Suppose that a group of plastic organisms is placed under new conditions. Those whose innate plasticity is not equal to the occasion are eliminated. . . . Such modification takes place generation after generation, but, as such, is not inherited. . . But any congenital variations similar in direction to these modification will tend to support them, and to favour the organism in which they occur. Thus will arise a congenital predisposition to the modifications in question. The plasticity still continuing, the modifications become yet further adaptive. Thus plastic modification leads, and germinal variation follows; the one paves the way for the other. The modification, as such, is not inherited, but is the condition under which congenital variations are favoured and given time to get a hold on the organism, and are thus enabled by degrees to reach the fully adaptive level.'"

Perhaps the fact that the two different germs of germcells are blended—that is, different from father and mother—may prevent us getting sufficient evidence to make us accept one or ether theory of those two schools of Evolution. There is another school called the Mendelian, and Von Vries' Mutation Theory is an alteration of or an addition to Mendelism. The Mendelists reject the Modification Theory of the Darwinians; they believe in mutations of changes, but they say they do not come about by slow or small variations but that there are "leaps or saltations." McCabe, in his book on Evolution, gives an illustration of what the Mendelians mean by change. He says that if we take a piece of wood with many sides and apply a small force to it, as it lies on one of its sides, it will tilt slightly and fall back to its original position. That would be called the fluctuation of a species. The fluctuations are, it is said, transmissible, but not the mutations. There, then, is the difference. Does evolution work by fluctuations according to Darwin, or by mutations according to Mendel? Dr Jordan says, after experimenting to discover the effect of the Mendelian Theory, that his results show inconsistencies with Mendelian laws, and that the theory is not yet proved. McCabe thus sums up the dispute:—"At the present time we can only say that a large number of instances of mutations, both among plants and animals are known, but they romain insignificant in number as page 6 compared with fluctations. It remains to be seen whether the future will materially add to them. Meantime, two facts should be borne in mind. The supposed intrinsic difference between a mutation and a fluctation is purely speculative, and we find variations of every intermediate length. It is therefore held by many that the difference is only one of degree, and that no strict line can be drawn between the two supposed classes. It is probable enough that natural selection works with both, according to the circumstances. The second fact is that we now generally recognise that the rate of evolution is by no means uniform. There have been periods of quicker and slower development, and the fossil evidence connects the former plainly with large changes in the environment. It thus appears that the conflict of fact on the new issue that has been raised is not necessarily irreconciliable. A glance down the stream of human history quite confirms this. Primitive man made astonishingly little progress for ages, and then, during the third glacial period in Europe, advanced rapidly. Since the dawn of civilisation the historical and ethnographical record is a similar chronicle of stagnation or slow or rapid advance, according to surroundings. It is, perhaps, advisable to close this survey of a world of controversy with a small summary. On the whole we have not penetrated very far or very confidently into the causes of variations—into the mysteries of embryology. We do not yet know how far the environment influences the germs, and if acquired modifications are in any sense transmitted to offspring. There is no general agreement as to the facts, which are not simple, and no theory of heredity commands anything like the general allegiance of the authorities. To base social creeds or experiments on any of them at present is hazardous; to assert, as Mr G. B. Shaw does, that 'the bubble of heredity, the inheritance of acquired modifications) has been pricked' is to ignore a very imposing array of living embryologists and zoologists; and the prevailing fashion of appealing to us to stake all on the germcells and pay less attention to environment and education is not justified in the state of science. It is true only that 'probably the majority' of the authorities do not admit the inheritance of acquired variations, but how far the environment (which in this case means everything but the germplasm) may influence the germs is still lees settled. Amphimixis, or the coalescence of two parent germs, is one admitted cause of variation; germinal selection is held by many to be a second cause. Variations may be large or small or intermediate, and its the more general belief that any of them may be selected. In fine, we have gained wider evidence that large variations exist, and some useful suggestions as to their causes, but every existing theory of heredity is sectarian and much disputed. Only the fact of evolution by the natural selection of ill-understood variations is established.

Thompson and Geddes's summary on Darwinianism may also be referred to (Evolution, p. 160): "There are here three main propositions:—(1) Variability is a fact of life. Variations are of frequent occurrence, and some of them are certainly transmissible. (2) Living creatures are very prolific. The majority die young. There is a ceaseless struggle for existence and the web of inter-relations is such that even minute variations may determine survival. (3). If variations occur in the direction of increased fitness, if the variations are transmissible, and if there is discriminate selection the possessors of the fitter variations are bound to be favoured with longer life and larger families—with survival, in short. If this is kept up consistently, then new adaptations, and, probably with the help of some form of isolation, new species, will arise."

It is therefore clear that though there is a difference of opinion amongst biologists as to the mode in which evolution works, all admit that there is evolution or development, and that the existing life, both vegetable and animal, have come from ancestors very unlike their descendants.

I have here a diagram taken from Sir Norman Lockyer's work on "Inorganic Evolution," which illustrates the growth of inorganic substances and shows the time it has taken for the hottest stars to cool. The degrees of heat (centigrade) are given on the one side and the stars on the other, and the time may be judged by this, that organic evolution which has taken perhaps thousands of millions of years is represented by the short point at the end, whilst the time taken for the growth of matter, as we know it on our Earth, has taken the enormous and unthinkable time represented by the long line.

Time of inorganic evolution compared with organic evolution.

Organic evolution occupies only a point in the line representing the time and temperature range required by inorganic evolution.

You will see that the stellar periods are borrowed from the names of typical bright stars, or of constellations in which such bright stars are found. There are some stars that are increasing in temperature, and some that are said to be decreasing in temperature. You will recognise the names of stars and constellations such as Argo, which is the name of a constellation, Algol, the name of a star, Cygnus the Swan, a constellation, Arcturus, a star in Bootes, Antaros, a star of the constellation of Scorpio. Arcturus is said to be about in the same state of heat as our sun, which is therefore in the third class of stars metallic. The word "proto-hydrogen" is used in describing the hottest stars, two stars in the constellation of Argo. Now the lines seen the spectrascope are not found anywhere else. Nothing we know of produces these lines, but they bear a likeness to hydrogen lines, and they are supposed to be the ancestors—if I may apply a word used in describing organic things, of hydrogen. The other lines seen with the "spectroscope are those of hydrogen when it is sparked with an electric coil in a vacuum tube. There are also faint lines of helium, proto-magnesium, and proto-calcium—that is, we may say, the helium not properly developed, and forerunners of magnesium and calcium. In the next series, the Crucian and Taurian, Argonian and Algolian, we have helium predominant, with hydrogen and spectral lines of the ancestors of proto-carbon, oxygen and nitrogen. Up to this time there were no traces of iron, copper, magnesium, nickel and other metals. In the proto-metallic stars like Rigel, and in some stars in the constellation of the Swan, we have again the ancestors or forerunners of metals such as lines akin to those of iron, copper, etc. We have to see, however, the metallic stars Polar, Procyon, Aldebaran and Arcturus, or our sun, before the true lines of iron, manganese are clear as seen in a voltaic arc, and in the last class the fluted spectra of carbon, etc. with fainter metallic lines are seen. What do scientific men make of these observations? They say that the beginnings of the constituents of matter are in the hottest stars, and that as the temperature falls this matter is formed into bodies such as metals, and by experiments made by physicists and chemists they are able to break up atoms by high tension electricity in a vacuum tube, and by the aid of the X-rays they can see a disintegration of metals, etc., into previous elements. Professor Moore, in his book on "The Origin and Nature of Life" says:—"The whole tale of elemental evolution holds together, is consistent, and leads to new discoveries. This is the distance which stellar observation and the study of radioactive matter take us on our journey; from this point the way lies amidst ordinary chemical combinations or chemical compounds. There is no breach of continuity as we enter this zone, the same laws of interaction hold, but greater specific differences in the forms of matter arise; there is more chemical individuality, and there are new conditions of energy manifestation."

There is therefore, you will see, an evolution of what are called inorganic compounds. You will have noticed that I have mentioned helium gas stars. The history of the discovery of helium is one of the most interesting incidents in science. There were observed in the spectroscope lines from the sun a substance that was unknown on the earth—that is, that no substance had given the same lines. It was called helium, by Lockyer, because it came from helios, the Greek word for the sun. Professor Ramsay and Lord Rayleigh discovered Argon, and the professor, in searching amongst minerals for proof of the Argon group of gases, tested a mineral called Cleveite, which, when heated, gave off gases, A minute amount of gas was put in a vacuum tube sparked with an electrical coil, and the spectrum of the spark gave the lines of Lockyer's helium. Since then helium has been found in many things. If radium is disintegrated it is found that what is called the alpha particles are nothing but charged helium which had therefore been a portion of elemental radium.

There is another phase of this subject of what is matter that I must [unclear: alude] to. At one time we had an atomic theory. According to Dalton there were particles in matter which were indivisible, and they were called atoms; they were, it is said one and structureless. This theory is not now accepted, for what were supposed to be elements and atoms have been disintegrated, and most men of science think that atoms are built up of electrons, and that therefore the basis of all matter is electricity. It would take some time to state to you the most recent results regarding the corpuscular theory of matter, and to rehearse to you all we know of electrons and their wonderful action. page 8 May I refer you to Sir J. J. Thomson's work on the subject, to Mr Cameron's book on Radio-Electricity, and Professor Duncan's work on the "Xew Knowledge." It has been found that the element radium can can give on disintegration, another element, helium, and thus in one case the dream of the old Alchemists has come true—transmutation has been accomplished, and this knowledge has been turned to use for rubies and small microscopic diamonds have been manufactured. Now, what does all this discussion lead to but this, that there is only one primal substance from which all the inorganic substances we have and all organic life have come. In the fiery mass of, say, the nebula of Argo, there is not only the potentiality of iron and other metals but also the potentiality of life. Dr. Charles Bastian has lately reiterated what he maintained years ago against Huxley, that he can get living organisms from the inorganic. His mode of procedure was to take a mixture of inorganic constituents such as sodium silicate, ammonia phosphate, dilute phosphoric acid and distilled water, and also sodium silicate and pernitrate of iron in distilled water. He sterilised these mixtures by raising them to a temperature of from 110deg. to 115deg. centigrade—that is higher than boiling point—in hermetically sealed tubes. He then kept those tubes for six months, exposing them to the rays of the sun, etc. He says that after an examination at the end of this period he found micro-organisms such as myxo-cocci, torulae, vibriones and moulds. All these are what are termed living things. Few scientific men at present accept his experiments as proving that these microorganisms have come from his mixtures. The vast majority say that these micro-organisms may have got into his mixtures from without. Professor Moore says that further experiments are being made, and the proper attitude of scientific men must be one of patience, and waiting for further proofs of Dr. Bastian's statement. He also states that if life is to originate it may originate in what is called colloids, which are gelatinous or gluey substances such as gum arabic, and which are not unlike Dr. Bastian's second mixture. That life may have been evolved in past times, and may not now be evolved would not be surprising, because the physical state of matter that existed millions of years ago differs from the physical state of matter now as our world has cooled. A celebrated chemist, Thomas Graham, who was Professor of Chemistry in Glasgow University, and afterwards Master of the Mint, said that matter might be classified into crystalloids and colloids, and he said, speaking of matter in the form of colloidal solution; "Their peculiar physical aggregation with the chemical indifference referred to, appears to be required in substances that can intervene in the organic processes of life. The plastic elements of the animal body are found in this class. As gelatin appears to be its type, it is proposed to designate substances of the class as colloids, and to speak of their peculiar form of agregation as the colloidal condition of matter. Opposed to the colloidal is the crystalloidal condition. Substances affecting the latter form will be classed as crystalloids. The distinction is no doubt one of intimate molecular constitution. 'Although chemically inert in the ordinary sense, colloids possess a compensating activity of their own, arising out of their physical properties. While the rigidity of the crystalline structure shuts out external impressions, the softness of the gelatinous colloid partakes of fluidity, and enables the colloid to become a medium for liquid diffusion, like water itself.' 'Another and eminently characteristic quality of colloids is their mutability. Their existence is a continued metastasis. A colloid may be compared in this respect to water while existing liquid at a temperature under its usual freezing-point, or to a supersaturated saline solution. Fluid colloids appear to have always a pectous modification; and they often pass under the slightest influence from the first into the second condition. The colloid is, in fact, a dynamical state of matter; the crystal-loidal being the statical condition. The colloid possesses energia. It may be looked upon as the probable primary source of the force appearing in the phenomena of vitality. To the gradual manner in which colloidal changes takes place (for they always demand time as an element) may the characteristic protraction of chemico-organic changes also be referred."

There is one question to be remembered, that if we examine the chemistry of our bodies we will see that the substances found in any living body are all substances found in what is termed matter. For example, the substances of sea-water consits of chloride of sodium, chloride-magnesia, sulphate of magnesia, sulphate of calcium, sulphate of potassium, bromide of magnesium and carbonite of calcium, and in the air we have nitrogen, oxygen and carbonic acid as page 9 its main elements. Now we know that in our bodies there is oxygen, nitrogen, carbon, hydrogen, sodium, potassium, phosphorous, sulpher, calcium, chloride and bromide and iron and silicate. All the substances, therefore, in our bodies are found in what is termed water and air.

There have been many suggestions as to the origin of life. It is clear that if evolution is true, varying kinds of inorganic substances can and do arise from some primitive substances, and so do different organic forms of life from primitive forms of organic life. No scientific man, as I have before said, accepts the theory that there was a special creation of every distinct inorganic substance and of every species of organic Ufe, No one says that there was a special horse, ass, dog, lion, cat, etc. created. On the contrary, all say that from small beginnings have come all these highly organised beings. How then came life? One suggestion made many years ago by Helmholtz and by Lord Kelvin in his address to the British Association in 1871 was that life came from another planet or from a meteorite. Lord Kelvin, then Sir William Thomson, said:—"When two great masses come into collision in space, it is certain that a large part of each is melted; but it seems also quite certain that in many cases a large quantity of debris must be shot forth in all directions, much of which may have experienced no greater violence than individual pieces of rock experience in a landslip or in blasting by gunpowder. Hence, and because we all confidently believe that there are at present, and have been from time immemorial, many worlds of life beside our own, we must regard it as probable in the highest degree that there are countless seed-bearing meteoric stones moving about in space. If at the present instant no life existed upon this earth, one such stone falling upon it might, by what we blindly call natural causes, lead to its becoming coverea with vegetation."

But this is no answer to the question—What is the origin of life. It is simply putting the question a little further back, for we must ask how did life originate in this meteorite or in this planet or in this sun from which it came to our world. Arrhenius has given a similar answer to the origin of life by suggesting that life of the most minute character, which was too minute to be able to be seen by the most powerful microscope may be in the form of sperms in the atmosphere and may live in ether and so reach this world, but this also leaves unanswered how did these living organisms come into our atmosphere, and from whence have they arrived. I may add that it would take over 50,000,000 years for a meteorite travelling 60 miles an hour to reach our earth from the nearest star. Alpha Centauri. A celebrated Swiss botanist, who lived up to 1869, namely, Naegeli, takes a different view of the origin, and he boldly says that it must be assumed that life has come from what we term the organic, but which is an inapt phrase to use if it be that there is one primal substance in the universe. He says (see page 173 of Moore) "If in the physical world all things stand in casual connection with one another, if all phenomena proceed along natural paths, then organisms, which build themselves up from and finally disintegrate into the substances of which inorganic nature consists, must have originated primitively from inorganic compounds. To deny spontaneous generation is to proclaim a miracle." And Huxley at Liverpool in 1870 at a meeting of the British Association said, as criticising Dr C. Bastian's experiments:—"But though I cannot express this conviction (i.e. the impossibility of organisms appearing in hermetically sealed and sterilised flasks) too strongly, I must carefully guard myself against the supposition that I intend to suggest that no such thing as abiogenesis (that is generation without life) over has taken place in the past, or ever will take place in the future. With organic chemistry, molecular physics, and physiology yet in their infancy, and every day making prodigious strides. I think it would be the height of presumption for any man to say that the conditions under which matter assumes the properties we call "vital" may not some day be artificially brought together.

All these considerations show that nothing is stable, that there is everywhere change, though time is great. What is the end to be? We do not know. At one time it was thought that our world would become, as astronomers tell us the moon has become, a frozen world without life, that is life of the kind at all events wo know in this world. Those who had the pleasure of listening, now over 30 years ago, to Proctor's lecture on the Moon, will remember the belief of astronomers then. I have pointed out to you that some stars are increasing in temperature while some are decreasing. And what of our Earth—may it not increase in temperature? Mr Soddy, the lecturer on Radioactivity in the University of Glasgow, thus sums up the position:—"It has in its known material constituents a steady source of fresh heat, which will page 10 last, not for one million, but for thousands, or tens of thousands of millions of years. It is regarded as more probable to-day, that instead of the earth becoming colder by radiation, as has been supposed, it is steadily growing hotter and hotter in its interior. The heat so generated throughout the mass, on account of the low conductivity of the rocks and materials forming the crust, only very slowly reaches the surface. At the surface, the heat generated escapes by radiation and maintains the temperature uniform. But the interior is almost completely thermally isolated from the surface, and the temperature within, provided that the composition of the materials is similar to that on the surface, must steadily be increasing. Joly has made some interesting calculations of the inevitable results that must attend such a process. Assuming a quantity of radium, and its corresponding amount of uranium, distributed uniformly through the mass of the earth, of two parts of radium per million million, which is less than the average found for surface rocks, this would produce an increase in the temperature of the interior by 1800 degrees centigrade, in a hundred million years. So long as the earth's crust remained solid, this heat would only escape by conduction with extreme slowness. But at some time or other, a world so constituted must explode, when the increasing temperature and pressure within overpowers the strength of the crust. According to the same authority, there is no assurance that such a consummation does not await the future, nor evidence that such has not more than once been an event of the past."

This view has importance in another way. You may remember in the early days of the evolution discussion, physicists like Lord Kelvin said that the geologists demanded so much time for the growth of the world that evolution could not be true. They asked millions and millions of years, and the earth had not existed so long, for it had cooled in a certain time. But now, as will be seen, the discovery of radium had made us alter all our views of the age of the earth. Now the earth may not only have existed for hundreds of millions of years in its present condition, but perhaps for thousands of millions of years, and the evolutionists may get any time they desire.. Before radium was discovered, the greatest age the physicists would give our earth was a hundred million years; now it may be many thousands of millions. Nature is on a vaster scale than our imagination can grasp.

What then may be said is the conclusion of the whole matter? It seems to me to be this: we have discovered after many hundreds of years of search that the universe that we are in—and I include in the universe not only the sun and its planets, our earth and others, but the universe as seen by us by our astronomers through the telescope and tested by the spectroscope, etc.,—has passed and is passing through change, and that our earth records that there has been a change in organic life—a development or evolution, as we may term it. If we are to accept the results of the investigations in astronomy and in physics and chemistry, we must believe that there has also been evolution in the inorganic world—that what we now see as metals in our earth have developed from gases of a simple type, and in the end we must be driven to come to the conclusion that in the beginning of things there is one primal substance from which inorganic matter in all its varieties and organic life in all its various forms have alike come. This seems to be the message that science delivers to us to-day, and Mr Balfour in his discussion on this subject in an address before the British Association has said that is a thought that must excite even our enthusiasm and our imagination that out of one thing has come all the wonders by which we are surrounded. Of course there lies behind all this discussion a further question which may lead us into what is termed the religious sphere. Where did this primal substance come from? That is outside, really, the domain of science. If we can discover that there is one primal substance from which both matter and life and matter and mind have come, may we not get a higher idea, a more loftier conception of the universe than we have had by the stories that have been told us of special creation? That is a matter for our consideration. All that I have attempted to do is to set before you what is the answer that science at present gives to the question—What is the origin of life, and the answer is that the origin of life is the same as the orgin of matter—there must have been one primal substance from which both have been derived. We cannot get any further. How that original primal substance came into being I do not think we can ever know We will have to pro-claim ourselves in that respect ignorant. The function of page 14 science is to ascertain what we can discover and what we can verify. It seems to me that science has so far discovered that there is one primal substance and it has also suggested at all events, that life may not only have developed millions of years ago in a distant sun or even on earth but that it may be developing now, on our earth, and that amongst the colloids simple forms of life not capable perhaps of being seen by the most powerful [unclear: mik-roscope] may be forming. Modern science of to-day has altered our ideas of the Atomic theory; it has given us much information about what we call elements; it has given us a different view of life. Who can say that science has now come to an end of its discoveries, and that there are not many other (to use a phrase that has often been used) continents of knowledge yet to be discovered? The attitude of the scientific men is to prove all things and to be dominated with the struggle to obtain the truth. That may be to man the highest ethical education of which he is capable.

Books That Should be Referred to.

Judd's The Coming of Evolution, Cambridge Manuals; Soddy's, Matter and Energy, Home University Library; Thomson and Geddes Evolution, Home University Library; Moore's, The Origin, and Nature of Life, Home University Library; Scott's, The Evolution of Plants, Home University Library; McCabe's, The Principles of Evolution, Collin's, The Nature Library; Duncan's, The New Knowledge, Hodder and Stoughton; Thomson, The Bible of Nature; Clarke, The System of Stars; Cameron, Radio-Chemistry; Dr C. Bastian, The Origin of Life; Lockyer'a, Inorganic Evolution.