The Chatelaine and the Enigma - Odell James

This is a steampunk story set in 1850. A dangerous revolutionary has been arrested and imprisoned in the Tower of London. He boasts that no conventional prison can hold him. He threatens to use magic to escape. The Guild of Magicians must use their own magic in attempt to restrain him. In another factory accident, workers have been killed. The government seems to be indifferent to the deaths. Can the authorities prevent another riot? The British government, confident the country's engineering skills, has sent an airship across the Atlantic. In New York, conspiracy theorists warn that the airship is a threat. In New York, too, riots are frequent. City politicians think they can benefit from violence, Anyone who appears to have British sympathies is under threat. The British consul and his daughter try to prevent the violence from escalating.