The value of the principles on which Rudyerd had conducted his work was abundantly proved by the fact, that his lighthouse continued to brave the force of the storms for upwards of forty-six years, and at the end of that period was destroyed, not by water, but by fire. This sad calamity happened on the 2nd of December, 1755. It has never been possible fully to investigate the cause of the building taking fire, but it appears to have commenced in the very top of the lantern or cupola. As the whole building was of wood, it is possible that the heat of the candles in the lantern, continued during the long period of between forty and fifty years, might have brought the thin boards which lined the cupola to such a state of dryness and inflammability, that, together with the soot which encrusted it, and which was formed from the smoke of the candles, it might have been as liable to take fire as a mass of tinder, and a single spark from one of the candles would be sufficient to effect the mischief. The light-keepers themselves attributed the fire to the copper funnel of the kitchen chimney which passed through the cupola. However this might be, the three light-keepers alone remained in the edifice, and when one of them, whose turn it was to watch, went into the lantern at about two o'clock in the morning to snuff the candles he found a dense smoke, and upon his opening the door of the lantern into the balcony, a flame instantly burst from the inside of the cupola. The man alarmed his companions, and they used their utmost endeavours to extinguish the fire, but on account of the difficulty of getting a sufficient supply of water to the top of the building, they soon found their efforts vain, and were obliged to retreat downwards from room to room as the fire gathered strength. Early in the morning the fire was perceived by some fishermen, and intelligence being given, a boat and men were sent out to the relief of the poor light-keepers. The boat reached the place at ten o'clock, after the fire had been burning eight hours. The light-keepers had been driven not only from all the rooms and the staircase, but to avoid the red hot timber, and the falling of the bolts upon them, they had been forced to creep into a hole or cave on the east side of the rock, where they were found almost in a state of stupefaction. There was great difficulty in getting them off the rock, for the surf was too high to enable the boat to effect a landing; but the men themselves becoming conscious of their perilous situation, and of the efforts that were being made to save them, adopted the only means of escape which now remained. By great efforts, a small boat had been got near enough to throw a coil of rope upon a projection of the rock, and the sufferers had sufficient remaining energy to lay hold of it, and one by one to fasten it round their bodies and jump into the sea. Thus they were towed into the small boat, and thence delivered to the large one, which returned with them to Plymouth. No sooner, however, were they set on shore than one of them made off, and was never afterwards heard of. This suspicious circumstance would naturally induce the idea that the man had himself originated the conflagration; but the fact of its being a lighthouse with no means of retreat for the inmates, and every reason to believe that they must perish with the building, is much opposed to this idea. In giving an account of this circumstance, Smeaton says, 'I would rather impute his sudden flight to that kind of panic which sometimes, on important occasions, seizes weak minds; making them act without reason, and in so doing commit actions whose tendency is the very reverse of what they desire.'