Book,  Chapter

1        I,  XI  |  on board to elucidate the origin of this catastrophe, it
2        I,  XV  |  tremendous an effect. The origin of the catastrophe was a
3        I,  XVII|    likely, to be of recent origin they concluded, from its
4        I,  XIX |  precipitous cliffs, of an origin and a substance alike unknown.~
5        I,  XXII| other minerals of volcanic origin with which the base of a
6       II,  XII |   evidently been of recent origin, dating probably only from
7       II,  XII |   probably of quite recent origin, because the comet before
8       II,  XV  |    as a satellite, and the origin of the whole of which is