  A vast majority of bright comets between the late 2nd century and the early
18th century, moving in potentially Kreutz orbits according to Hasegawa &
Nakano (2001), was first sighted between 2 and 16 days after perihelion, thanks
to the spectacular tails that they were then displaying. In this paper I
examine the basic properties of the post-perihelion tails of the three
brightest Kreutz sungrazers of the 19th and 20th centuries -- the Great March
Comet of 1843 (C/1843 D1), the Great September Comet of 1882 (C/1882 R1), and
Ikeya-Seki (C/1965 S1). As the pre-perihelion tail of a sungrazer sublimates
completely at perihelion, the development of its post-perihelion tail starts
from scratch. In the early days after perihelion, the tail length grows rapidly
on account of the plasma component. At some point the dust takes over, reaching
a peak length weeks later. As the geocentric distance continues to increase and
the surface brightness to decline, the tail's shortening sets in. The dust
tails of Ikeya-Seki and the 1843 sungrazer contained grains subjected to solar
radiation pressure accelerations not exceeding 0.6-0.7 the solar gravitational
acceleration, the dust tail of the 1882 sungrazer was more complex. For weeks
this comet appeared like a comet in a comet, a result of disintegration of a
distant companion near perihelion. Evening Kreutz sungrazers are found to have
longer tails than morning ones because of geometry. Other issues are discussed
and extensive sets of tail data are provided.
