It is supposed that astronomic subjects and principles and methods cannot be understood by the layman. I think this, myself. We shall take up some of the principles of astronomy, with the idea of expressing that of course they cannot be understood by the unhypnotized any more than can the stories of Noah's Ark and Jonah and the Whale be understood, but that our understanding, if we have any, will have some material for its exercises, just the same. The velocity of light is one of these principles. A great deal in the astronomic system depends upon this supposed velocity: determinations of distance, and amount of aberration depend. It will be our expression that these are ratios of impositions to mummeries, with such clownish products that formulas turn into antics, and we shall have scruples against taking up the subject at all, because we have much hard work to do, and we have qualms against stopping so often to amuse ourselves. But, then, sometimes in a more sentimental mood, I think that the pretty story of the velocity of light, and its "determination," will some day be of legitimate service; be rhymed some day, and told to children, in future kindergartens, replacing the story of Little Bopeep, with the tale of a planet that lost its satellites and sometimes didn't know where to find them, but that good magicians came along and formulated the indeterminable.
It was found by Roemer, a seventeenth-century astronomer, that, at times, the moons of Jupiter did not disappear behind him, and did not emerge from behind him, when they "should." He found that as distance between this earth and Jupiter increased, the delays increased. He concluded that these delays represented times consumed by the light of the moons in traveling greater distances. He found, or supposed he found, that when this earth is farthest from Jupiter, light from a satellite is seen 22 minutes later than when nearest Jupiter. Given measurement of the distance between opposite
points in the earth's supposed orbit, and time consumed in traveling this distance—there you have the velocity of light.
I still say that it is a pretty story and should be rhymed; but we shall find that astronomers might as well try to formulate the gambols of the sheep of Little Bopeep, as to try to formulate anything depending upon the satellites of Jupiter.
In the Annals of Philosophy, 23-29, Col. Beaufoy writes that, upon Dec. 7, 1823, he looked for the emergence of Jupiter's third satellite, at the time set down in the National Almanac: for two hours he looked, and did not see the satellite emerge. In Monthly Notices, 44-8, an astronomer writes that, upon the night of Oct. 15, 1883, one of the satellites of Jupiter was forty-six minutes late. A paper was read at the meeting of the British Astronomical Association, Feb. 8, 1907, upon a satellite that was twenty minutes late. In Telescopic Work, p. 191, W. F. Denning writes that, upon the night of Sept. 12, 1889, he and two other astronomers could not see satellite IV at all. See the Observatory, 9-237—satellite IV disappeared 15 minutes before calculated time; about a minute later it re-appeared; disappeared again; re-appeared nine minutes later. For Todd's observations see the Observatory, 2-227—six times, between June 9 and July 2, 1878, a satellite was visible when, according to prediction, it should have been invisible. For some more instances of extreme vagaries of these satellites, see Monthly Notices, 43-427, and Jour. B. A. A., 14-27: observations by Noble, Turner, White, Holmes, Freeman, Goodacre, Ellis, and Molesworth. In periodical astronomical publications, there is no more easily findable material for heresy than such observations. We shall have other instances. They abound in the English Mechanic, for instance. But, in spite of a host of such observations, Prof. Young (The Sun, p. 35) says that the time occupied by light coming from these satellites is doubtful by "only a fraction of a second." It is of course another instance of the astronomers who know very little of astronomy.
It would have been undignified, if the astronomers had taken the sheep of Little Bopeep for their determinations. They took the satellites of Jupiter. They said that the velocity of light is about 190,000 miles a second.
So did the physicists.
Our own notion is that there is no velocity of light: that one sees a thing, or doesn't; that if the satellites of Jupiter behave differently according to proximity to this earth, that may be because this earth affects them, so affecting them, because the planets may not, as we may find, be at a thousandth part of the "demonstrated" distances. The notion of velocity of light finds support; we are told in the text-books, in the velocity of sound. If it does, it doesn't find support in gravitational effects, because, according to the same textbooks, gravitational effects have no velocity.
The physicists agreed with the astronomers. A beam of light is sent through, and is reflected back through, a revolving shutter—but it's complex, and we're simple: we shall find that there is no need to go into the details of this mechanism. It is not that a machine is supposed to register a velocity of 186,000 miles a second, or we'd have to be technical: it is that the eye is supposed to perceive—
And there is not a physicist in the world who can perceive when a parlor magician palms off playing-cards. Hearing, or feeling, or if one could smell light, some kind of a claim might be made—but the well-known limitations of seeing; common knowledge of little boys that a brand waved about in the dark cannot be followed by the eyes. The limit of the perceptible is said to be ten changes a second.
I think of the astronomers as occupying a little vortex of their own in the cosmic swoon in which wave all things, at least in this one supposed solar system. Call it swoon, or call it hypnosis—but that it is never absolute, and that all of us sometimes have awareness of our condition, and moments of wondering what it's all about and why we do and think the things that sometimes we wake up and find ourselves doing and thinking. Upon page 281, Old and New Astronomy, Richard Proctor awakens momentarily, and says: "The agreement between these results seems close enough, but those who know the actual difficulty of precise time-observations of the phenomena of Jupiter's satellites, to say nothing of the present condition of the theory of their motions, can place very little reliance on the velocity of light deduced from such observations." Upon pages 603-607, Proctor reviews some observations other
than those that I have listed—satellites that have disappeared, come back, disappeared, returned again so bewilderingly that he wrote what we have quoted—observations by Gorton, Wray, Gambart, Secchi, Main, Grover, Smyth-Maclear-Pearson, Hodgson, Carlisle, Siminton. And that is the last of his awareness: Proctor then swoons back into his hypnosis. He then takes up the determination of the velocity of light by the physicists, as if they could be relied upon, accepting every word, writing his gospel, glorying in this miracle of science. I call it a tainted agreement between the physicists and the astronomers. I prefer mild language. If by a method by which nothing could be found out, the astronomers determined that the velocity of light is about 190,000 miles a second, and if the physicists by another method found about the same result, what kind of harmony can that be other than the reekings of two consistent stenches? Proctor wrote that very little reliance could be placed upon anything depending upon Jupiter's satellites. It never occurred to him to wonder by what miracle the physicists agreed with these unreliable calculations. It is the situation that repeats in the annals of astronomy—a baseless thing that is supposed to have a foundation slipped under it, wedged in, or God knows how introduced or foisted. I prefer not to bother much with asking how the physicists could determine anything of a higher number of changes than ten per second. If it be accepted that the physicists are right, the question is—by what miracle were the astronomers right, if they had "very little" to rely upon?
Determinations of planetary distances and determinations of the velocity of light have squirmed together: they represent either an agreeable picture of co-operation, or a study in mutual support by writhing infamies. With most emphasis I have taken the position that the vagaries of the Jovian satellites are so great that extremely little reliance can be placed upon them, but now it seems to me that the emphasis should be upon the admission that, in addition to these factors of indeterminateness, it was, up to Proctor's day, not known with anything like accuracy when the satellites should appear and disappear. In that case one wonders as to the state of the theory in Roemer's day. It was in the mind of Roemer that the two "determinations" we are now considering first
most notably satisfied affinity: mutual support by velocity of light and distances in this supposed solar system. Upon his Third Law, which, as we shall see later, he constructed upon at least three absences of anything to build upon, Kepler had, upon observations upon Mars, deduced 13,000,000 miles as this earth's distance from the sun. By the same method, which is the now discredited method of simultaneous observations, Roemer determined this distance to be 82,000,000 miles. I am not concerned with this great discrepancy so much as with the astronomers’ reasons for starting off distances in millions instead of hundreds or thousands of miles.
In Kepler's day the strongest objection urged against the Copernican system was that, if this earth moves around the sun, the stars should show annual displacements—and it is only under modern "refinements" that the stars do so minutely vary, perhaps. The answer to this objection was that the stars are vastly farther away than was commonly supposed. Entailed by this answer was the necessity of enlarging upon common suppositions generally. Kepler determined or guessed, just as one pleases, and then Roemer outdid him. Roemer was followed by Huygens, with continued outdoing: 100,000,000 according to Huygens. Huygens took for his basis his belief that this earth is intermediate in size to Mars and Venus. Astronomers, today, say that this earth is not so intermediate. We see that, in the secondary phase of development, the early astronomers, with no means of knowing whether the sun is a thousand or a million miles away, guessed or determined such distances as 82,000,000 miles and 100,000,000 miles, to account for the changelessness of the stars. If the mean of these extremes is about the distance of present dogmas, we'd like to know by what miracle a true distance so averages two products of wild methods. Our expression is that these developments had their origin in conspiracy and prostitution, if one has a fancy for such accusations; or, if everybody else has been so agreeable, we think so more amiably, ourselves, that it was all a matter of comfortably adjusting and being obliging all around. Our expression is that ever since the astronomers have seen and have calculated as they should see and should calculate. For instance, when this earth's distance from the sun was supposed to be 95,000,000 miles, all astronomers taking positions of Mars,
calculated a distance of 95,000,000 miles; but then, when the distance was cut down to about 92,000,000 miles, all astronomers, taking positions of Mars, calculated about a distance of 92,000,000 miles. It may sound like a cynicism of mine, but in saying this I am quoting Richard Proctor, in one of his lucid suspicions (Old and New Astronomy, p. 280).
With nothing but monotony, and with nothing that looks like relief for us, the data of conspiracy, or of co-operation, continue. Upon worthless observations upon the transits of Venus, 1761 and 1769, this earth's orbit was found by Encke to be about 190,000,000 miles across (distance of the sun about 95,000,000 miles). Altogether progress had been more toward the wild calculations of Huygens than toward the undomesticated calculations of Roemer. So, to agree with this change, if not progress, Delambre, taking worthless observations upon the satellites of Jupiter, cut down Roemer's worthless determinations, and announced that light crosses the plane of this earth's orbit in 16 minutes and 32 seconds—as it ought to, Prof. Young would say. It was then that the agreeably tainted physicists started spinning and squinting, calculating "independently," we are told, that Delambre was right. Everything settled—everybody comfortable—see Chambers' Handbook of Astronomy, published at this time—that the sun's distance had been ascertained, "with great accuracy," to be 95,298,260 miles
But then occurred something that is badly, but protectively, explained, in most astronomical works. Foucault interfered with the deliciousness of those 95,298,260 miles. One may read many books that mention this subject, and one will always read that Foucault, the physicist, by an "independent" method, or by an "absolutely independent" method, disagreed somewhat. The "disagreement" is paraded so that one has an impression of painstaking, independent scientists not utterly slavishly supporting one another, but at the same time keeping well over the 90,000,000 mark, and so essentially agreeing, after all. But we find that there was no independence in Foucault's "experiments." We come across the same old disgusting connivance, or the same amiable complaisance, perhaps. See Clerke's History of Astronomy, p. 230. We learn that astronomers, to explain oscillations of the sun, had decided that the sun must be, not
That the word "worthless" does apply to observations upon transits of Venus:
In Old and New Astronomy, Proctor says that the observations upon the transits of 1761 and 1769 were "altogether unsatisfactory." One supposes that anything that is altogether unsatisfactory can't be worth much. In the next transit, of 1874, various nations co-operated. The observations were so disappointing that the Russian,