Dear friends and dear Scott. I have two questions. In this films I saw that staysails and two of upper square sails of Surprise was open on the calm sea. Why all the sails dont open? For controlling the speed of ship? I know that in storm stay sails are closed. My another question is, in the film, why upper square sails open? Why lower sails don´t open? What is the difference?
If you give information I will be happy.

Ihsan Oktay Anar

I´ll do my best to answer.

In the film on the clam sea (I´m assuming you are referring to the scenes in the doldrums) it would have been common practise to set all sails, for several reasons:

1) to dry them - sails back then would have been made of natural fibres and were susceptible to molds and rot - so especially after stormy weather - setting them on a calm dry day was good prevention - it also bleaches them in the sun - and crews were very proud of the ´look´ of their ship!

2) to catch any bit of wind possible - by setting all sail, any wind that did happen to come up could be caught - so it was in some respect just a "just in case" type of set for the sails.

But you are correct, under normal sailing conditions you would rarely have both squares and staysails set at the same time.

As for when in a storm and otherwise a ship´s master may choose to set some sails and not others would depend both on wind conditions and their goals... be it flight or fight, or perhaps just safe sailing...

For example , when riding out a storm - typically just the staysails (or sometimes just one even) would be set - to provide just enough way to keep the ship´s head.

However, the master may risk more sail if matters pressed - like in the movie where they were either running from, or trying to catch their enemy.

Finally - to answer what is the difference between the "upper" (topsails) and "lower" (course or main sails)

Topsails are smaller, and would frequently be used in a storm when running (especially if they were reefed or shortened) this provided less sail area then using course sails (which are designed for sailing in the trade winds or under calmer conditions) the main reason is that in a storm, if you tried to set the course sails - it would likely cause either them, or the mast itself, to be carried away.

does that help at all?