As a result of the first invasion, warriors began ordering polishers to
grind off the ha-niku, making a sharper edge-profile. During this time, the
Soshû school of sword-making came into its own. In this new tradition, a
piece of steel plate was welded to an iron rod and beaten to a thin rectan-
gle, marked across, and folded. This was beaten again to the same dimen-
sions as before, the folding and beating process repeated up to fifteen times.
Next, four such pieces were welded together to create a thicker plate, and
again the cutting, folding, and beating process was carried out, this time for
five repetitions. In this manner the individual layers being worked fifteen
times gives 32,768 laminations in geometrical progression, the final number
Sword, Japanese 567Carl McClafferty and
Tosho (swordsmith)
Ezawa Toshiharu
examine metal to
be used in a sword,
April 1994.
(Courtesy of Carl
McClafferty)