The Siege of Charleston.
Charleston, Dec. 11th.
--Twelve shells were thrown into the city last night, at intervals of three hours. Damage trifling.--Our batteries replied.
No firing on Sumter.
[second Dispatch.]
Charleston, Dec. 11 P. M.
--The enemy again shelled the city at intervals during the day. Six buildings were struck, but no person injured.
About 9 o'clock this morning Fort Sumter took fire from some cause as yet unknown.
The fire communicated to some outer timber work of the southwest angle, and the wood work was burned and some ammunition destroyed.
There were some casualties, but the particulars have not yet been received.
The enemy's land batteries opened heavily on the fort during the progress of the fire, and were replied to from Moultrie and our batteries.
A heavy firing was kept up all day, which ceased at dark.
Damage to Sumter not material. 