The conclusion of the Wardenclyffe Trilogy
Time travelers are stranded in the Gilded Age in the company of an Ozark Granny, a time-traveling goat, a pair of Gypsy fortune tellers, and a homing pigeon that flies across time and space. They seek Nikola Tesla at the 1893 World's Columbian Exposition. They need Tesla's technology, and they aren't above using any means to get it. A fanatic from the future is desperate to stop them and the cost may be the fair itself: the fulcrum point upon which the 20th century totters.
Hail Columbia!