Jim Southward, captain of the Harbor Queen, warned his passengers politely and then sounded one long and three short blasts of his very loud horn.
"Draw up the gangplank. Cast off," he called to the crew.
Yoga classes don't usually start this way.
This was yoga on a boat. A very large boat. The double-decker Harbor Queen, celebrating its 41st birthday this year, makes several 40-minute circuits of the Annapolis harbor each day in the summer. But it is usually filled with tourists or schoolchildren on a field trip.
But on Saturday and Sunday mornings in June and July, it will carry those who will look to combine the meditative peace of their yoga practice with the serene beauty of summer on the water in the Severn River.
"Why wouldn't you do yoga on a boat?" asked the teacher, Kathleen Schuman of Annapolis' Prana Yoga Studio. This was her first such class.
"The purpose of yoga is, literally, to create space. In the body, in the mind, in life," she said. "What better place to do it than in this beautiful space?"
The Harbor Queen is a very stable boat, assured the captain. There isn't much rocking, certainly not at 8:30 on a weekend morning. The regular sailors are just gearing up. So it isn't like doing yoga on a rowboat or a paddle board.
"The challenge is theirs," said Schuman, when asked if she would have to adapt her instruction to the possibility that the surface from which her students would try to draw their stability might be moving underneath them.
"Their challenge is to let go of what they expect and just go with what is happening on their mat."
There were about 30 students Saturday morning, the first day of this season's session, but the Harbor Queen can accommodate 50 students and their mats. One class can be held on the top deck and a second underneath on the covered deck.
Last year, the Saturday classes, sponsored by Living Social and Watermark, which owns the Harbor Queen and 12 other touring boats, sold out almost immediately. Sunday classes were added this year.
"Early morning. Energetic people. On the water," said April O'Brien of Watermark, which also arranges floating weddings, parties and rock bands. "You get a much different Zen."
The class costs $49 through Living Social and it includes an hour of yoga and another hour of touring, docking back in Annapolis at about 10:30 a.m. Coconut water is free, but the cash bar on board opens after class.
"Last year, we had these groups of women friends from around Washington who would come for yoga, go out to brunch and then shop in Annapolis," said Kendra Hansen, Living Social event manager.
Chris Pham, 25, a dental student at the University of Maryland and a newcomer to yoga, was looking for a birthday gift for Clara Gomez, 26, a medical school student who is also new to yoga.
"I love the idea that it is on a boat," said Gomez. "Now I don't want to go back inside."
Krista Romer had her friend, Donna Ripple, apply spray sunscreen to her back and shoulders before class began — another thing that doesn't happen in a regular yoga class. The two women from Fulton also asked for restaurant suggestions for their day in Annapolis.
"It was great," said Ripple, who had worried about balance poses before class begin. "I would do it again."
Instructor Schuman pronounced the class a success — and she learned the names for parts of the boat so she could give the correct verbal instructions to her students: port, starboard, bow and stern.
Southward, who declined to take any credit for the smooth ride, announced to his passengers at the end of the cruise that he would be docking the Harbor Queen "in downward dog pose."
"There is a comforting effect from this kind of cruise," he acknowledged.
"I mean, I had 240 fourth-graders on a trip this week."
@SusanReimer on Twitter.com
If you go
Cost: $49 through Living Social (livingsocial.com/events/cities/529-annapolis)
When: 8:15 a.m. to 10:30 a.m. Saturdays and Sundays, through July 21. (Rain dates: July 27, 28)
Where: Harbor Queen, docked at the end of the pier on Ego Alley in Annapolis Harbor.
Details: Bring your own yoga mat. For more information, call 877-521-4191.