[DiogenesLamp]

[BroJoeK]

reference to DL's map, post #275.

Here's that description of Beauregard's 46 cannon:

"Beauregard, a trained military engineer, built-up overwhelming strength to challenge Fort Sumter.

Fort Moultrie had
1. three 8-inch Columbiads,
2. two 8-inch howitzers,
3. five 32-pound smoothbores, and
4. four 24-pounders.

   Outside of Moultrie were

5. five 10-inch mortars,
6. two 32-pounders,
7. two 24-pounders, and
8. a 9-inch Dahlgren smoothbore.

   The floating battery next to Fort Moultrie had

9. two 42-pounders and
10. two 32-pounders on a raft protected by iron shielding.

    Fort Johnson on James Island had

11. one 24-pounder and
12. four 10-inch mortars.

    At Cummings Point on Morris Island, the Confederates had emplaced

13. seven 10-inch mortars,
14. two 42-pounders,
15. an English Blakely rifled cannon, and
16. three 8-inch Columbiads, the latter in the so-called Iron Battery, protected by a wooden shield faced with iron bars.

About 6,000 men were available to man the artillery and to assault the fort, if necessary, including the local militia, young boys and older men."[31]

By my count, that's 46 total Confederate cannon.
But the key is that Lincoln's commander, Gustavus Fox, believed he could land resupplies at Fort Sumter under cover of darkness and tried the night of April 12.
Weather was not calm enough, so they intended to wait for the next night, the 13th.

"During the darkness, the Confederates reduced their fire to four shots each hour."

Four shots per hour in the dark would not make it impossible for Fox's resupply boats to reach Fort Sumter.
But by the next night, Major Anderson had already surrendered, Fox's mission failed.