Month: June 2015

Samuel J. Gummere’s Lecture on Copernicus

In 1862 Samuel J. Gummere began lecturing on astronomy at Haverford College. At that time all sophomores and juniors heard lectures based on John Herschel’s Outlines of Astronomy; seniors heard lectures on “practical astronomy” based on Elias Loomis’s text (probably his Introduction to Practical Astronomy) and carried out observations in the college’s new observatory.

The college was quite proud of its new observatory, that cost nearly $7,000 to build and outfit with instruments. (See also the notice in the Haverford College Catalogue. 1862–1863, where they emphasize students using the instruments.)
The college was quite proud of its new observatory, that cost nearly $7,000 to build and outfit with instruments. (See also the notice in the Haverford College Catalogue. 1862–1863, where they emphasize students using the instruments.)

Gummere’s lecture notes survive in Haverford’s Quaker & Special Collections[1] and give a tantalizing glimpse into the nature of astronomy education in the middle of the 19th century. Through the opening two dozen or so pages of Gummere’s notes he covers the history of astronomy from ancient Greece up to the “modern era.” Although his lectures were structured largely by chronology, he detoured into astronomical instruments for at least a lecture.

Unsurprisingly, Gummere thought Copernicus had established modern astronomy. Equally unsurprising is Gummere’s dismissive comment about the Islamic astronomy, whose greatest contribution was to preserve ancient astronomy “through the long ages of darkness, and again restoring [it] to the nations of Europe.”
Unsurprisingly, Gummere thought Copernicus had established modern astronomy. Equally unsurprising is Gummere’s dismissive comment about the Islamic astronomy, whose greatest contribution was to preserve ancient astronomy “through the long ages of darkness, and again restoring [it] to the nations of Europe.”

For Gummere and, consequently, his students, modern astronomy began with Nicholas Copernicus and the publication of his De Revolutionibus Orbium Coelestium. Whereas previous philosophers had speculated about a heliocentric system, their work had been mere guesses and had failed to persuade anybody. Copernicus, however, grounded his heliocentric system in new observations (according to Gummere) and better mathematics. As a result, those who could understand Copernicus’s arguments were immediately persuaded. Yet many who couldn’t understand the arguments continued to invoke commonsense experience and tradition to oppose Copernicus’s system.

Gummere was quick to point out that neither the Church nor the pope were immediately opposed to the heliocentric system.[2]

Gummere’s discussion of Copernicus sounds much like a basic introductory course and does not instill much confidence in the level of astronomy instruction at Haverford College in the 1860s. Perhaps these were merely background lectures before students confronted contemporary astronomy.[3]

Here, for your reading amusement, is Gummere’s lecture on Copernicus and the dawn of modern astronomy:

We have thus in a few sentences dispensed of many centuries of astronomical history but we have shall henceforth find ourselves embarrassed by the abundance rather than by the scarcity of materials We come now to what is considered the modern era introduced by the reformation in theoretical astronomy brought about chiefly by the researches and the labors of one whose name will always be prominently associated with the establishment of the true system of the universe.
Nicolas Copernicus was born at Thorn in Prussia in the year 1473—While engaged in the study of medicine at the University of Cracow his mind was constantly directed to mathematical subjects—He afterwards went to Italy and received last lessons in astronomy from the celebrated professor Dominic Ferra Maria after which he spent some time in teaching mathematics and in making astronomical observations at in Rome Returning to his native country he devoted himself almost exclusively to the study and the practice of astronomy His dwelling is said to have been situated on the summit of a mountain commanding an uninterrupted prospect of the heavens, and hence most favorably situated placed for his chosen pursuit—The attention of Copernicus was now strongly turned to the prevailing theory in relation to the celestial motions—The absolute immobility of the earth as the central body of the universe was at this time universally admitted—This was supported by the apparent evidence of the senses, by the supposed testimony of scripture and by the authority of such philosophers as Plato and Aristotle—In earlier ages indeed, different systems had been proposed advocated at various times but these systems were mostly based on mere random guesses, and were never seldom supported by any arguments entitled to any attention—
Among the various conjectures as to the celestial mechanism it would be a matter greatly to be wondered at if the Sun had never been selected as the centre of the planetary motions, and indeed there is evidence that many philosophers of little celebrity adopted this view—The name of Pythagoras however is generally associated with this true system of the world as the first man of uni acknowledged eminence through there is some reason to believe that it was first advocated by his immediate followers and not by himself—But the ipse dixit of Pythagora[sic] was not powerful enough to question a system seemingly so paradoxical it fell into oblivion.
Copernicus was disposed to find simplicity and harmony rather than complexity and disorder in the system of the universe, and was thus gradually led to the opinions adopted the Pythagorean doctrine that the sun is immovable in the centre of the system and that his real apparent annual motion is the result of the revolution of the earth as a planet and with the other planets around their common centre: the diurnal motion being produced by the earth’s daily rotation on its axis—
We can scarcely conceive at this day how startling such views assigning not merely a single but a two fold motion to the earth must have been to those whose belief in the earth’s its [sic] absolute immobility resting on the evidence of their senses informed by lay centuries of unquestioning acquiescence—The Prussian Astronomer however was in no haste to divulge his opinions or to gain converts—He resolved to find support for his theory in more accurate observations of the planetary movements than had yet been made—He accordingly constructed a large quadrant with movable radii with which he made an immense number of observations.
Though now fully confirmed in his belief of the correctness of his theory, Copernicus was yet reluctant to shock the prejudices of the world by publishing the work which he had been deliberately preparing to justify his conclusions—One of his friends, however, prepared the way for him by publishing anonymously an account of the new system—About the same time also the author of a work called Theorica novae Planetarum alluded to the want of a second Ptolemy to restore the degenerate science of the age and alluding to Copernicus expressed the hope that such a person would be found in Prussia—
Being thus encouraged in relation to the reception that his views were likely to meet with, Copernicus ventured to publish his own carefully prepared work, which was printed in the year 1543 when its distinguished author had all just completed his three score years and ten—The following was is the title of this celebrated book the publication of which marks an era in astronomical science—“Nicolai Copernici Toriniensii de Revolutionibus Orbium Coelestium libri VI. Habes in hoc opere jam recens nato et edito, studiose lector, motus stellarum tam fixarum quam erraticarum, cum ex veteribus tum etiam ex recentibus observationibus institutus[4] et novis insuper ac admirabilibus hypothesibus ornatos[5]. Habes etiam tabulas expeditissimas ex quibus eosdem ad quodvis tempus quam facillime calculare poteris. Igiture eme, lege et fruere.
Copernicus did not live to enjoy the celebrity of his publication of to be disturbed by the opposition which it called forth. He did not even read his own work in print the first copy having been placed in his hands only a few hours before his death—It has been remarked as a singular circumstance that Copernicus the author of so great a reformation in science should have had no sympathy with the great reformer in religion but that on the other contrary the district in which he lived stood alone among the surrounding districts in its hostility to Luther and his doctrines.
The theory of Copernicus was at once embrace adopted by the greater part many of those who were able to understand the fore reasonings by which it was supported, nor did it encounter that opposition from the Church Pope which its author seems to have apprehended —thefrom the Church which had not yet taken alarm at the innovations and heresies of science—
It is no matter of wonder however that the old system should still maintain its ground for a time with persistent obstinacy—Indeed Copernicus and his supporters were not in a position to prove the truth of the new doctrine—The grounds on which alone it could then be supported were its plausibility, its simplicity, and the satisfactory explanation which it furnished of all the celestial motions—the last quality however it only shared with that system which made the earth the centre of the all the celestial motions and regarded the planets as satellites of the sun and attending him in his annual revolution about the earth[6]—It has been said that this latter system though mechanically absurd is yet astronomically correct—and even the adoption of it at this day would not require any change to be made in our tables of or our modes of calculation—The struggle, then, with those who balanced the two theories was between the simplicity of the one, and the weight of authority with the testimony of the bodily senses to the truth of the other—
Many years later Bacon who always opposed the new theory thus argued against it: “In the system of Copernicus there are many and grave difficulties: for the threefold motion with which he encumbers the earth is a serious inconvenience: and the separation of the sun from the planets with which he has so many affections in common is likewise a harsh step: and the introduction of so many immovable bodies into nature, as when he makes the sun and stars immovable, the bodies which are peculiarly lucid and radiant: and his making the moon adhere to the earth in a sort of epicycle: and some other things which he assumes are proceeding, which mark a man who thinks nothing of introducing fictions of any kind into nature provided his calculations turn out well”—
Gilbert who distinguished himself by his experiments and researches in magnetism after weighing the arguments in favor of the Copernican system comes to the conclusion that the system in partly true, that is that the earth revolves on its axis, and this revolution he connects with his magnetic hypotheses, yet he hesitates to admit the annual revolution of the earth—The prevailing uncertainty and indecision in relation to the Copernican theory and its rival is well set forth by Milton in his discourse between Adam and the Angel Raphael…

  1. For those interested, Gummere’s lectures are Call #910F.  ↩

  2. Though he suggests that the Church would before long oppose science. It will be interesting to see what he says, if anything, about Galileo and the Church.  ↩

  3. In another set of notes that treat modern phenomena, e.g., meteor showers, however, he adopts a similar historical-survey approach.  ↩

  4. He glossed it as “founded”  ↩

  5. He glossed it as “supported”  ↩

  6. Here Gummere alludes to the Tychonic system, which he seems to dislike.  ↩