The latter is the best of the three, that of 1566 only a reprint of the editio princeps of 1543. There is only one difference: that of 1543 has an ample errata … which disappears in 1566 without any of the errors being corrected. This is all corrected in 1617 and moreover the text has been rectified in many places; also there are notes by the editor and some very useful examples of calculations. Book lovers can prefer the editio princeps, which is on beautiful paper and which is larger and has more body, with letters on the figures less tiny, but astronomers must use the edition of 1617. This is why I keep two examples. I had the edition of 1566, but gave it up.—J. B. J. DELAMBRE, DIRECTOR OF THEPARIS OBSERVATORY, 1804–1822, FROM A COMMENTTACKED INSIDE A 1566 COPY OF On the RevolutionsThe condemnation of Copernicus’s ideas by the Roman Church, which would have devastated the Catholic canon had he lived to hear of it, probably served to make his book more popular. Only one year after the Edict of 1616 connected his name with the crime of heresy, a third edition of On the Revolutions appeared in Amsterdam, under the title Astronomy Renewed.
