Bones in the Badlands (Time Spies #2)

When Alex, Mattie, and Sophie touch the spyglass, they find themselves hurtled back to 1898, where real-life dinosaur cowboy Walter Granger has a job for them. Granger has discovered a secret cache of dinosaur skeletons. But someone's trying to steal the bones for himself. Can the Time Spies catch the thief before the spyglass sends them home?