Schiller, Julius. Coelum stellatum Christianum. Augsburg, 1627.
Schiller's Christian Starry Heavens was aptly named, for in this atlas, Schiller replaced all of the pagan constellations with Christian counterparts. The twelve zodiacal constellations, for example, were renamed for the twelve apostles; so that Taurus the Bull, for example, became St. Andrew. Other notable replacements include The Red Sea for the river Eridanus; the Ark of Noah for the Ship of the Argonauts (below), and the Sepulcher of Christ for Andromeda.
Each plate in Schiller's atlas is slightly smaller than the corresponding plate in Bayer's work, but the plates are in the same order. Opposite each plate (rather than on the verso as in Bayer) is a printed table, where the stars are identified by Arabic numbers, rather than Bayer letters. Schiller also gives two descriptions for each star, one with reference to the pagan constellation figure and one for the new Christian replacement.
If we compare a detail of the Schiller's Andrew plate (left) with the corresponding section of Bayer's Taurus plate (right), we can see that Schiller was rather clever in his redesign work; the Hyades, which so nicely outline the face of the Bull in Bayer, seem equally appropriate in forming the V-shape of Andrews cross. We also notice another noteworthy feature of Schiller's atlas: the stars on the plates are in mirror-image positions from those in Bayer. Schiller preferred to show the stars as if they were placed on a globe, that is, from the outside, rather than as viewed from the earth.
Engraving Style in Coelum Stellatum Christianum
A final point that seems to have been escaped historical notice concerns the engraving style used for Schiller's plates. The engraver, Lucas Kilian, was quite a distinguished artist, and he utilized for this atlas a brand new technique, invented shortly before in Italy, in which shading was produced by swelling the engraved line.
Most star-map engravings produce shading by using cross-hatching, or, as in Bayer's Uranometria, a stipple technique. Swelling the engraved line to produce shading is a much more uncommon style, since it requires great skill in wielding the burin, but it is particularly effective in rendering the folds of billowing draprey, and so quite suitable for depicting constellation figures.