Snowman dresses the part, wearing a bonnet and long dress to reflect how women dressed in 1783 when the Commonwealth of Massachusetts rebuilt the tower that was blown up by retreating British troops in 1776, as the Revolutionary War got underway.
Twice a day she walks the island's perimeter to inspect its buildings, making sure that the light is still drawing power from an undersea cable stretching from the mainland, and that the island's water and communications systems work properly.
In between, she oversees a crew of about 100 volunteers who help to take weather readings and fill the hundreds of tiny holes that pock the island, thanks to a population of muskrats.
Automation is not the only change facing lighthouses.
As navigators rely on other technologies to find their way, the U.S. government has begun selling or donating to historic preservation groups lights no longer necessary for navigation.
More than 300 lights have passed into private hands this way, according to Coast Guard officials.
But for recreational boaters and small fishing vessels, which represent a sizable chunk of Boston Harbor traffic, the lights still play a role.
"They help with approaches because they can be seen from a great distance away," said David Bryan, general manager of the Boston Sailing Club, which teaches sailing and navigation.
"If the idea is that now everyone is using GPS and you don't need light houses, I would say that redundant information is very important when navigating."
Beyond its role in navigation, Boston Light is also a tourist draw. Snowman has a theory as to why.
"For many, it has a sense of hope and spirituality, not religion, but spirituality," she said in an interview atop the tower, looking out over Boston Harbor. "They look at it and see it as a coming home and safety."
