Often, during even ordinary gales of wind, the whole structure was completely covered by the water, so that when the waves rose the light could not be seen.  Having inspected the holes in which the towers stood, we examined the cellar.  It was cut out of the solid rock, and is twenty feet long by eight wide, and four feet deep, and has a covering of granite eight inches thick, the entrance being by two gun-metal doors, or rather man-holes, perfectly impervious to water when closed; it was formed to hold the tools and stores of the labourers.  The rock itself is twelve feet above the level of the sea at high-water, and the lantern of the old lighthouse stood seventy feet above the water.