I learned afterwards from some of the prisoners, who went into Charleston ahead of us, and were camped on the race course outside of the City, that one day our fellows threw a shell clear over the City to this race course.

There was an immediate and terrible panic among the citizens.

They thought we had mounted some new guns of increased range, and now the whole city must go.

But the next shell fell inside the established limits, and those following were equally well behaved, so that the panic abated.

I have never heard any explanation of the matter.
It may have been some freak of the gun-squad, trying the effect of an extra charge of powder.