Conflagrations.
Leavenworth, Dec. 17.
--A portion of the town of Platte City, Missouri, including the Court-House and Post-Office, was destroyed by fire last night.
It was set on fire about 1 o'clock by the rebels, but the flames were suppressed by the troops under Col. Morgan.
At 4 o'clock the town was again successfully fired.
The county records were saved, but the office was destroyed.
Many arrests were made, including some of S. Gordon's Guerilla Band and one of Price's Captains.
Buffalo, N. Y., Dec. 17.--The warehouses formerly occupied by the Michigan Central Railroad, together with the propeller Dunkick, lying at the dock, were destroyed by fire this morning.
Five hundred barrels of flour in the warehouses were burned.
The loss on the propeller was $18,000. The other losses have not as yet been ascertained.