At this point, the pursuit slowed because Thomas had sent his pontoon bridge train towards Murfreesboro rather than Franklin and Columbia, and his artillery and supply trains could not cross the Harpeth River until the pontoon train arrived. This did not stop Wilson's cavalry from aggressively pursuing the Confederates as they retreated to Columbia. Wilson badly hurt Carter L. Stevenson's rearguard division in actions on December 17 and 18, but was forced to stop because of the lack of supplies. Wilson's problems were compounded when Forrest and his two cavalry divisions arrived in Columbia from Murfreesboro on December 18.