2. What is the central message of Boston Light?

Well the person above seems to know!

The structure built by Massachusetts in 1716 was a circular, slightly tapered tower of rubble stone about 60 feet (18.29 m) high, the light provided by candles. Also constructed were a keeper's house, barn, and a wharf. A fog cannon was installed in 1719. (After being discontinued in 1851, it was removed from the island by the Coast Guard in 1962 and returned in 1993.) The tower was damaged by fires started by the light in 1720 and, more seriously, in 1751 and by a severe storm in 1723. Each time as well as in 1734-37 the tower was repaired or rebuilt. The most significant damage, however, occurred during the Revolutionary War. On July 20, 1775, when the British occupied Boston and held Boston Light, patriot troops burned the wooden parts of the tower. The British began to repair it, whereupon the Americans burned it again on July 31 and again in September. Finally, in June 1776, as the last of the British were leaving Boston, they blew up the lighthouse (Snowman and Thomson 1999:7, 11, 13-14, 97-100; Snow 1971:44). Boston Light was not rebuilt by Massachusetts until 1783. This time it was again circular, constructed of mortared rubble stone, and 75 feet (22.86 meters) high with the illumination provided by four fish oil lamps. In 1809, when lighthouses were under the purview of the secretary of the treasury, large cracks appeared in the east wall and six iron hoops were then installed around the tower for support. (Today there are five, the sixth having been removed sometime between 1917 and 1935. The present aluminum bands replaced corroded steel ones in 1973-74.) In 1811 a revolving mechanism was installed to create a flashing light. During the Pleasonton years the condition of the lighthouse apparently deteriorated but improvements were also made-a chandelier with 14 lamps and reflectors was installed in 1828 and the present cast iron stairs, iron window frames, balcony, and large iron door added in 1844. And in 1851 the fog cannon was replaced by a wind-up bell (Snowman and Thomson 1999:14, 24-25, 26, 29, 30, 70, 158, 161-62, 182)