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.
A folyosó szája majdnem teljesen kör alakú volt, az átmérője másfél méter lehetett. Sziklába vágott fala teljesen sima volt, úgy látszik, valamikor erre ömlött ki a láva.