In this hall, lectures were given to inmates to provide spiritual
relief and religious teaching, as well as to cultivate their moral character. Christian
ministers and Buddhist monks preached moral principles to inmates, endeavoring to reform them.
According to a story passed down from generation to generation, the inmates put all their
heart and soul into completing the Lecture Hall. The half-hipped roof is made of roofing
tiles called sangawara. The roof framework was built by using large-span queen post roof
trusses in which king post trusses were placed above two-tiered transverse beams. The bottom
beams in the roof framework and posts were secured by using angle braces. Consequently, a large
space without posts was created in the Lecture Hall. The Lecture Hall is floored in wood.
There are small rooms on the side of the stage and on both sides of the hall. The walls in the
hall are finished with a plaster-like white material, and wainscoting is used. The ceiling is
double-corniced, and three round ornaments are placed at the center of the ceiling. Clapboards
and wainscoting are applied to the exterior walls, and posts are exposed at the four corners.
Each double-hung widow has a comb-shaped pediment. The roof rafters that make up the eaves fan
out at each corner where the eaves are bent upwards. A unique fish-shaped ornament with fins and
a leaf design, or a sacred fish called hiretsuki gekyo, is attached to the gable. This
building blends Japanese and Western designs and techniques. The design details of this building
attest to the Ministry of Justice's high level of technical expertise in architectural
design and construction when the building was built.