The aperture, which was almost round, was about five feet in diameter; the dark passage was cut out in the live rock and lined with a coat of the eruptive matter which formerly issued from it; the interior was level with the ground outside, so that we were able to enter without difficulty.
L'orifice, à peu près circulaire, présentait un diamètre de cinq pieds environ; le sombre tunnel était taillé dans le roc vif et soigneusement alésé par les matières éruptives auxquelles il donnait autrefois passage; sa partie inférieure affleurait le sol, de telle façon que l'on put y pénétrer sans aucune difficulté.