PORT TOWNSEND — With a brisk breeze blowing down the bay, the RV Mary Beth set sail Sunday on a voyage of discovery — into the past.

The Mary Beth is a fishing boat-turned-research vessel operated by the Menzies Project to conduct environmental monitoring of local waters.

To subsidize the scientific side, the crew takes people cruising on Port Townsend Bay, birdwatching around Protection Island and, this year, teaming with the Jefferson County Historical Society to offer waterfront tours that show Port Townsend history from a different perspective.

“When you’re on a walking tour of Water Street, you don’t see much water,” said Barbara Lea Wright, a historic re-enactor and tour leader.

“When you’re out here, you can see the whole waterfront. All the maritime history back to the sailing ships comes together.”

Wright and Lynne Sterling, both Jefferson County Historical Society volunteers, usually don Victorian costumes for the waterfront tours, which they led four times last summer as a try-out.

This year, they’re doing the tours every other Sunday, inviting Port Townsend Visitor Center volunteers for the inaugural run over the weekend.

MENZIES CRUISES, IN collaboration with the Jefferson County Historical Society, offers historical waterfront tours out of Port Townsend from 2 p.m. to 4 p.m. every other Sunday through Oct. 2

Cost is $40 for adults, $27 for children 4 to 17, with discounts for Jefferson County Historical Society members.

For more information, call 360-379-0378 or 888-379-0378, or go to www.menziesproject.org.

The historical society also offers walking tours of downtown Port Townsend that focus on military history, dastardly deeds, Victorian architecture and the railroad. Call 360-385-1003.