Hi Stewart,
I have found that Facebook now blocks public access to business and organization sites such as the museum's. If you don't have an FB account....and I don't, access is restricted. Going to the URL, FB begins by blocking part of the page and demanding either a login or a sign-up. As time goes on, the blocker basically eats up the entire page, making it nearly impossible to view the content. Another user was correct in that if you can click on a photo, the blocker will go away, but the moment you go back to the main FB page for the museum, access is once again blocked.
Personally, I think that in the process of trying to force people like me to given them phone numbers and e-mail addresses, the Facebook people are also hurting their existing subscribers by cutting out a substantial portion of their potential audience. Who knows, with brilliant moves like this, they could have a future just like MySpace....LOL!
/Kevin