The spread of the doctrine was also helped by Thomas Salusbury's translations of the books and passages condemned by the Index in 1616 and 1619. This collection, "intended for gentlemen," he published by popular subscription immediately after the Restoration,[367] a fact that indicates that not merely mathematicians (whom Whewell claims[368] were by that time all decided Copernicans) but the general public were interested and awake.[369]

The appearance of Newton's Principia in 1687 with his statement of the universal application of the law of gravitation, soon ended hesitancy for most people. Twelve years later, John Keill, (1671-1721), the Scotch mathematician and astronomer at Oxford, refuted Descartes's theory of vortices and opened the first course of lectures delivered at Oxford on the new Newtonian philosophy.[370] Not only were his lectures thronged, but his books advocating the Copernican system in full[371] went through several editions in relatively few years.

In the Colonies, Yale University which had hitherto been using Gassendi's textbook, adopted the Newtonian ideas a few years later, partly through the gift to the university of some books by Sir Isaac himself, and partly through the enthusiasm of two young instructors there, Johnson and Brown, who in 1714-1722 widened the mathematical course by including the new theories.[372] The text they used was by Rohault, a Cartesian, edited by Samuel Clarke with critical notes exposing the fallacies of Cartesianism. This "disguised Newtonian treatise" was used at Yale till 1744. The University of Pennsylvania used this same text book even later.[373]

In 1710 Pope (1688-1744) refers to "our Copernican system,"[374] and Addison (1671-1719) in the Spectator (July 2, 1711) writes this very modern passage:

"But among this set of writers, there are none who more gratify and enlarge the imagination, than the authors of the new philosophy, whether we consider their theories of the earth or heavens, the discoveries they have made by glasses, or any other of their contemplations on nature.... But when we survey the whole earth at once, and the several planets that lie within its neighborhood, we are filled with a pleasing astonishment, to see so many worlds hanging one above another, and sliding around their axles in such an amazing pomp and solemnity. If, after this, we contemplate those wide fields of æther, that reach in height as far as from Saturn to the fixed stars, and run abroad almost to an infinitude, our imagination finds its capacity filled with so immense a prospect, as puts it upon the stretch to comprehend it. But if we yet rise higher, and consider the fixed stars as so many vast oceans of flame, that are each of them attended with a different set of planets, and still discover new firmaments and new lights, that are sunk farther in those unfathomable depths of æther, so as not to be seen by the strongest of our telescopes, we are lost in such a labyrinth of suns and worlds, and confounded with the immensity and magnificence of nature.

"Nothing is more pleasant to the fancy, than to enlarge itself by degrees, in its contemplation of the various proportions which its several objects bear to each other, when it compares the body of man to the bulk of the whole earth, the earth to the circle it describes round the sun, that circle to the sphere of the fixed stars, the sphere of the fixed stars to the circuit of the whole creation, the whole creation itself to the infinite space that is everywhere diffused around it; ... But if, after all this, we take the least particle of these animal spirits, and consider its capacity wrought into a world, that shall contain within those narrow dimensions a heaven and earth, stars and planets, and every different species of living creatures, in the same analogy and proportion they bear to each other in our own universe; such a speculation, by reason of its nicety, appears ridiculous to those who have not turned their thoughts that way, though, at the same time, it is founded on no less than the evidence of a demonstration."[375]

A little later, Cotton Mather declared (1721) that the "Copernican hypothesis is now generally preferred," and "that there is no objection against the motion of the earth but what has had a full solution."[376] Soon the semi-popular scientific books took up the Newtonian astronomy. One such was described as "useful for all sea-faring Men, as well as Gentlemen, and Others."[377] "Newtonianisme pour les Dames" was advertised in France in the forties.[378] By 1738 when Pope wrote the Universal Prayer:

"Yet not to earth's contracted span
Thy goodness let me bound
Or think thee Lord alone of man,
When thousand worlds are round,"

the Copernican-Newtonian astronomy had become a commonplace to most well-educated people in England. To be sure, the great John Wesley (1770) considered the systems of the universe merely "ingenious conjectures," but then, he doubted whether "more than Probabilities we shall ever attain in regard to things at so great a distance from us."[379]

The old phraseology, however, did recur occasionally, especially in poetry and in hymns. For instance, a hymnal (preface dated 1806) contains such choice selections as: