Read-Parrott
The sulphur matrix used in the specimen above was often found to be
brittle and therefore crumbled during formation of the cavity, unlike coal-tar, which was
more flexible. Note that the bursting cavity was formed by drilling through the
case-shot material. A Federal Read-Parrott, 2.9-inch caliber projectile fitted with
a Bormann time fuze is rare. The 5 1/4-second burning time of the standard Federal Bormann time
fuze was insufficient for rifled artillery because its range was so much
greater than that of smoothbore cannon.