On the Bread Crust Bolmb From Shiro-yama Kagoshima City Japan

In this paper the writer reported the petrological study of the bread crust bomb, which was discovered for the first time by him from the Shirasu Bed, at Shiro-yama, Kagoshima city, with special references to the pumiceous block in the same bed, and of the plagioliparite, both of which formed the plateau in topography. Because a bomb is, in general, interpreted as the projected pieces of the lava torn in a molten state the bread crust bomb in question may be conceived to be the representative of the original magma, from which all the materials composing the Shirasu Bed are derived. According to the petrological data of these rocks previously given, it may be conclude that they are identical in genesis.