The Universe Around Us. By Sir James Jeans. New York: The Mac-millan Company. $4.50.
If this isn't farce of the broadest, what else can it be called? But Mr. Bowers does not hint at it.
Nevertheless, he has written an excellent book which is not only filled with salutary truth, but also with delight for the reader.
There grew in Wonderland a certain mushroom which Alice ate to change her size. Those who would enter into the wonderland described by Sir James Jeans must take with them some of this potent fungus. First it is a story of beyond and beyond and beyond. Let us eat and start to grow, and as we grow the earth and all the universe seems to shrink. When the earth has dwindled to the size of a golf ball, the sun, a ball some two hundred feet in diameter, is half a mile away, the nearest fixed star is a similar ball some sixty, thousand miles off.. Another bite, and the earth's orbit shrivels to the dimensions of a pin-head, the sun a tiny dust speck at the center, and the earth too small to be seen by any microscope. The nearest star is now another dust speck over two hundred yards away and if we scatter a few billion such specks a hundred yards or so apart we have the milky way, filling a flat pancake over five thousand miles across and about one tenth as thick. And still we have only begun. Beyond and beyond are other galaxies like this, millions of them, and we need about four million miles to include those we can see with our present telescopes, with no hint of an end in sight. And yet, if Einstein is right, there is an end, and sooner or later space comes back upon itself. Beyond and beyond—but if we go on a billion times as far as we can see, we find ourselves home again. It is a fascinating tale, this story of man's explorations of the starry skies, and it is mainly sober fact with little guess-work about it. And the author tells it simply and clearly.
But the astronomer today cannot concern himself wholly with these large matters. Like Dr. Johnson's poet he must be "conversant with all that is awfully vast or elegantly little," and the search for the elegantly little takes us into the atom, there to watch the little electrons at their play. We must eat from the other side of the mushroom and grow small, and the tale is now of within and within. We cannot claim for this part of the story the literal truth of our survey of space, our picture is more symbolic. But we know our scale of sizes pretty well. If we enlarge our golf ball to the size of the earth its atoms would be about the size of golf balls. Each of these is for the most part as empty as the solar system, consisting of a score or so of electrons just visible under the microscope whirling in incredibly rapid orbits (say a thousand million million times a second) about an equally tiny central nucleus, which plays the sun to all these planets. Strange as these tales of the infinitely small may seem, it is almost stranger still that the astronomer finds an application for them in his study of the stars. And here this story is brilliantly told.
For the land encountered in our next chapter, we get no help from Alice's mushroom, for now we must journey back in time. It is a tale of before and before and before. Uncounted ages ago there was perhaps a body of gas filling all space. The mathematician can show that this condition would be unstable, that owing to the gravitational attraction of one part of the gas for another it would tend to clot or curdle into separate masses of gas of about the size of a galaxy, and these in turn would clot or curdle into stars. By some such process as this our sun had reached nearly its present size and temperature about a million million years ago. The story, is devoid of news value until quite recently, not until about B.C. 2,000,000,000 when something happened which was unusual even in the milky way. Another star passed quite close to the sun, and damaged it by drawing out long filaments of hot matter which slowly condensed to form the planets. The next news item is three hundred million years back—the appearance of life on the earth. The old news files which are embedded in the rocks contain nothing of human interest, however, until about three hundred thousand years ago when man appeared. The last hundredth or so of this time represents recorded history, within which our present knowledge of the stars began; telescopic astronomy is only three hundred years old, and most of the facts and speculations with which this book deals are less than thirty years old. Such is the accelerated pace of the advance of science.
What are we to make of it all? Can we find new bottles to hold this heady wine? Can we relate this new knowledge to the daily round of our lives or must we fall back upon creeds outworn to find a place for our petty strivings. For one, I find thoughts difficult to formulate. The contemplation of the cosmos is inimical to discursiveness; in the presence of the stars there should be silence.
"A star that has no parallax to speak of Conduces to repose,"
and to gather in one's thoughts from the incredible vastness and to compress them into the compass of a few printed pages is too hard. Perhaps we shall get at things better from a more mundane angle, starting from an event in the here and now. A book has appeared—classifiable by librarians as popular science, sub-heading astronomy. Such an event may have little relevance to the fact that it will be read by the light of a very ordinary star some ninety million miles away. There are thousands of millions of such stars in our own galaxy (the possessive pronoun is really charming) and there are millions of such galaxies in the universe, whose owners, if any, as Mr. Dooley would say, "don't thravel in our set." But as the event is responsible for my writing these pages it may be worth our while to consider it. What is a book on popular science anyway, and why? Sir James Jeans has written a good many books, the distinguished excellence of which will win them the respect, but hardly the affection of the multitude. He now turns his hand to a bestseller. Why?
We might divide all authors into salesmen and missionaries. The first thinks of his fellow man as the possessor of money, the second as the possessor of a soul. The one seeks buyers, the other readers. I think we may safely assume our author to be a missionary, one who believes he has something to say to his fellow man which it is important for that man to hear. The problems which interest him seem tremendously important and he wants others to share his enthusiasm. . . . It may well be that he is also not insensible to popular acclaim. Monstrari digito is not an exalted ambition, but it marks the possessor as human, which is not such a bad thing in a great physicist. But the dominant desire is undoubtedly, to spread the knowledge of science, and particularly the scientific spirit, among the people. But can this be done?
It is easy enough to be a sensation monger, emphasizing the spectacular, and feeding a public avid of signs and wonders. This is all the newspaper reporter attempts; he would like to be accurate but he must above all be exciting. "The Universe Around Us" is all that the reporter could ask, but this is no fault of the author; the interest is inherent in his tale. He is painstakingly accurate, never dodging a difficulty for the sake of making things over-simple. His illustrations and descriptive analogies are a delight to the most knowing. But while he has told inimitably what the scientific man thinks, he has not succeeded so well in telling the public how he thinks, and it is only thus that the spirit of science can be taught.
In those other excellent but excessively non-popular works just mentioned, he writes for his equals; it is the facts that speak, and so far as he expresses an opinion or draws a conclusion these are subject to the criticism of competent judges. But in a popular work all this is changed. He is now Sir James Jeans, the eminent astronomer and physicist, speaking with the voice of authority to a public unable to weigh evidence. Of course there are degrees of ignorance both among scientists and laymen. But we can form some idea of the actual situation if we can imagine these different works to have been published anonymously. The standing of the technical works would hardly have been affected by the omission of the author's name; to the popular work the omission would be fatal. This is in no sense a specific criticism of the work before us. The author has failed where perhaps no man could have done better. The necessity of talking down to an audience vitiates completely the atmosphere of true scientific communication. To breathe this unpolluted, everyone—layman and expert—must go back to the sources. Such works as "The Origin of Species," or Faraday's "Journal of Researches" are fairly intelligible to anyone. The reader will no doubt learn from them much that is today held to be wrong, but he will learn rightly, and in the only right way, the spirit of science. There will probably be much that he will not understand, but this need not surprise him, for in their own day they were misunderstood. But what he gets will be genuine. Suppose next year some other eminent authority publishes an account of the universe differing radically from Sir James Jeans's version. The uninstructed will have some difficulty in seeing what the two writers have in common, but it is just this common element, namely their mode of approach to the problem, that has persisted through all the history of science. Not in the thing done, but in the manner of its doing does the spirit of science reside.
If I have seemed to criticise it has not been my, intention. When one considers the average, run-of-mine work on popular science it seems peculiarly ungracious to single out for attack one of the very best that has appeared in years. But it is only because it is one of the best that it shows clearly that one of the major objectives of the popularizer is unattainable.
One word of real criticism may be added. When the author ventures outside astronomy his critical faculty forsakes him, and he displays a mind typical of the eighteenth rather than the twentieth century; a mind self-contained within the mathematical realm and conscious of no limitations in its conclusions. Thus he finds no difficulty in foreseeing several billion years of life ahead on the earth, and even of human life, and of astronomy. The warrant for this belief is given by his calculations of the probable duration of present physical conditions. But human life has existed already, a bare three hundred thousand years and in this time has been changed almost beyond recognition. The uniformities which justify the physical prediction are absent from the biological problem. No dominant race of living creatures has lasted more than a tiny fraction of the time over which he extends his prophecy, and if we are justified in any conclusion it would be that we can understand as much about life on the earth three hundred million years hence as the amoeba can now comprehend about man, which isn't much. But these are only obiter dicta and should not be taken too seriously.