Hi Gerry: I'm a little late getting in on this. Usually family farms have multi-purpose barns that house machinery, animals and animal feed. If I recall correctly, the Kents had at least one cow, so Martha could be milking her and there could be hay bales around for feed. I think the Kents also had chickens, so she could be getting chicken feed for them or fertilizer for her vegetable garden.
As for the Ferry crossing, depends on the size of the ferry and which part ot the country. We have ferries going from the mainland to several of the San Juan Islands and from Anacortes, WA to Victoria, BC. There are also small ferries that move from island to island. The one CCM mentioned, from Maine to Nova Scotia, crosses an area noted for huge fluctuations in tides that could create a lot of churning. I've been hanging over the side in a small boat, myself, while passing between two islands when the tide was going one way, the wind was blowing another, and waves were caroming back and forth from land mass to land mass produing a stomach-emptying yawing and bouncing.
Hope that helps.
Jude
