Astrology & astronomy

Astrology (the application of knowledge gleaned from the stars) was the basis for weather predictions and anatomical information included in almanacs¹. The compilers of the early Harvard almanacs associated astrology with paganism and did not include weather predictions or anatomical information, focusing instead on astronomy² (the study of planets, moons, stars, and other celestial beings).

Astronomical content, particularly about eclipses, remained in New England almanacs even as astrological content began appearing by 1678³.

A common belief of the time held that the phases of the moon determined proper times for blood letting, which was used as a prescribed medical treatment for certain ailments and was practiced by many as a periodic cleansing activity. Before blood letting, readers would use an almanac to learn which sign the moon was in on a given day and which body part was governed by the moon. It was believed that a cut in or near the part of the body being influenced by the moon could lead to uncontrollable bleeding and even death. Some readers also believed that phases of the moon determined appropriate times to geld cattle, shear sheep, graft trees, fell timber, and slaughter swine⁴.

Examples of pages with astrological content are below. Some also include astronomical content on the same page, or entirely unrelated information. See the Man of Signs page in this exhibit for further astrology-related examples.

¹Madeleine Hudson, “Future Events We unto Thee Impart’: A Transatlantic Examination of Almanacs in the Seventeenth and Eighteenth Centuries” (Masters thesis, Tufts University, 2015), 16.

²Thomas A. Horrocks, “Rules, Remedies, and Regimens: Almanacs and Popular Medicine in Early America" (PhD dissertation, University of Pennsylvania, 2003), 38.

³Horrocks, “Rules, Remedies, and Regimens," 38.

⁴David Harold McCarter, “‘Of Physick and Astronomy’: Almanacs and Popular Medicine in Massachusetts, 1700-1764” (PhD dissertation, University of Iowa, 2000), 35-39.