1. In the context given, "While excitement was high over the depredations of the Barbary pirates" does not really express concern, but more so a feeling of piqued curiosity. Americans were very interested in the pirate attacks. They probably saw them as adventurous and exotic. The previous sentence "In the meantime, however, Americans continued to be fascinated by the remote." is what really implies this. Specifically the part "...Americans continued to be fascinated..." Sorry for my long winded explanation. I hope I didn't confuse you further. Please let me know if you need a different explanation. 2. "for the scurvy" means that the medicine was used to treat a disease called scurvy. Scurvy is a disease that occurs when a person does not have enough vitamin C. It was a very common maritime disease because it was hard for sailors to maintain a healthy diet while on a ship for many months at a time.