Soulfre is the largest and (40 most important of the whole series but it is inaccessible. (vent) (Illust. from 1903 photos) It lies within the Grande Fente where that fissure cleaves the solid lava from top to bottom of the north side of the cone. One can stand beside the fissure and look down into the cham- ber some eight or ten feet in diameter which seems to con- tain the principal vent, if there be more than one outlet for the steam. This chamber is beautiful, with its complete lining of sulphur in crys- tals. Below this chamber is another smaller room in which one can see pendant "stalactites.