Using records of individual depositors' accounts, this article provides a detailed microeconomic analysis of two banking panics. The panics of 1854 and 1857 were not characterized by an immediate mass panic of depositors and had important time dimensions. We examine depositor behavior using a hazard model. Contagion was the key factor in 1854 but it created only a local panic. The 1857 panic began with runs by businessmen and banking sophisticates followed by less informed depositors. Evidence suggests that this panic was driven by informational shocks in the face of asymmetric information about the true condition of bank portfolios.