stars and the signs of the zodiac on each
part of the body, as well as the parts of the anatomy suitable for
bleeding. These charts illustrated the veins and arteries that should be
incised to let blood for specific ailments and usually included brief
instructions in the margin. The annotated bloodletting figure was one of
the earliest subjects of woodcuts. One early and well known _Aderlassmann_
was prepared by Johann Regiomontanus (Johannes Mueller) in 1473. It
contained a dozen proper bleeding points, each suited for use under a
sign of the zodiac. Other _Aderlassmanner_ illustrated specific veins to
be bled. The woodcut produced by the sixteenth-century mathematician,
Johannes Stoeffer, illustrated 53 points where the lancet might be
inserted.[26]

"Medicina astrologica" exerted a great influence on bloodletting.
Determining the best time to bleed reached a high degree of perfection in
the late fourteenth and fifteenth centuries with the use of volvella or
calculating devices adopted from astronomy and navigation. These were
carried on a belt worn around the waist for easy consultation. Used in
conjunction with a table and a vein-man drawing, the volvella contained
movable circular calculators for determining the accuracy, time, amount,
and site to bleed for an illness. The dangers of bloodletting elicited
both civic and national concern and control. Statutes were enacted that
required every physician to consult these tables before opening a vein to
minimize the chance of bleeding improperly and unnecessarily. Consultation
of the volvella and vein-man was more important than an examination of the
patient.[27] (Figure 3.)

For several centuries, almanacs were consulted to determine the propitious
time for bleeding. The "woodcut anatomy" became a characteristic
illustration of the colonial American almanac. John Foster introduced the
"Man of Signs," as it was called, into the American almanac tradition in
his almanac for 1678, printed in Boston. Other examples of early American
almanacs featuring illustrations of bleeding include Daniel Leed's almanac
for 1693, printed in Philadelphia, and John Clapp's almanac for 1697,
printed in New York.

As in many of the medieval illustrations, the woodcut anatomy in the
American almanac consisted of a naked man surrounded by the twelve signs
of the zodiac, each associated with a particular part of the body (the
head and face with Aries, the neck with Taurus, the arms with Gemi