Valour and Vanity by Mary Robinette Kowal

Jane and David Vincent have been travelling with Jane’s family but now set out on their own to visit Venice and Murano in an alternate version of the early 1800s where magic works. The Vincents work with light and sound to create moving scenes called glamurals. Their ship is attacked by pirates, and David is injured. They arrive on the island of Murano with no money, documents, or luggage, and David’s friend Lord Byron is away. A banker from the ship offers them rooms and arranges for a line of credit while they look for glassmakers who will work with them to create glass globes with magic. When it appears that the banker has swindled them, the Vincents work with a puppeteer and a convent to unmask the criminals, clear their names, and get their papers back. Magic, Lord Byron, and a gondola race are all included, along with some romance. Their previous adventures are related in Without a Summer.
Brenda