Minot's Ledge is three miles off the mouth of Boston Bay, a jagged reef of granite, wholly submerged at high tide, and showing a scant hundred yards of rock above the water at the tide's lowest stage. It lies directly in the pathway of ships bound into Boston, and over it, on even calm days, the breakers crash in an incessant chorus. Two lighthouses have reared their heads here to warn away the mariner. The first was completed in 1848, an octagonal tower, set on wrought-iron piles extending five feet into the rock. The skeleton structure was expected to offer little surface to the shock of the waves, and the wrought iron of which it was built surely seemed tough enough to resist any combined force of wind and water; but in an April gale in 1851 all was washed away, and two brave keepers, who kept the lamp burning until the tower fell, went with it. Late at night, the watchers on the shore at Cohasset, three miles away, heard the tolling of the lighthouse bell, and through the flying scud caught occasional glimpses of the light; but morning showed nothing left of the structure except twisted stumps of iron piles, bent and gnarled, as though the waves which tore them to pieces had been harder than they. Then, for a time, a lightship tossed and tugged at its cables to warn shipping away from Minot's Ledge. Old Bostonians may still remember the gallant Newfoundland dog that lived on the ship, and, when excursion boats passed, would plunge into the sea and swim about, barking, until the excursionists would throw him tightly rolled newspapers, which he would gather in his jaws, and deliver to the lightship keepers to be dried for the day's reading. But, while the lightship served for a temporary beacon, a new tower was needed that might send the warning pencil of light far out to sea. Minot's was too treacherous a reef and too near a populous ocean highway to be left without the best guardian that science could devise. Accordingly, the present stone tower was planned and its construction begun in 1855. The problem before the designer was no easy one. The famous Eddystone and Skerryvore lighthouses, whose triumphs over the sea are related in English verse and story, were easier far to build, for there the foundation rock is above water at every low tide, while at Minot's Ledge the bedrock on which the base of the tower rests is below the level of low tide most of the year. The working season could only be from April 1 to September 15. Nominally, that is almost six months; but in the first season the sea permitted exactly 130 hours' work; in the second season 157, and in the third season, 130 hours and 21 minutes. The rest of the time the roaring surf held Minot's Ledge for its own. Nor was this all. After two years' work, the piles and debris of the old lighthouse had been cleared away, and a new iron framework, intended to be anchored in solid masonry, had been set, when up came a savage gale from the