There were two powder magazines constructed by Commander Stone, one on the extreme north of the property and one shown in the photo which is directly behind the storehouses which now hold the Museum. The first was begun in 1855 and the second in 1857 and were designed to hold three thousand barrels of powder each. Both structures were massive, vaulted buildings with stone walls four feet thick and heavy hipped roof.
The interior consisted of one large room divided by a row of columns. The interior walls were covered in wooden wainscoting probably to keep moisture from entering through the stone. Today, many examples of graffiti from as early as 1878 can be seen on these walls. Both magazines were built of the local sandstone which was quarried just to the right of the magazine pictured above. The magazines were virtually identical in design, however, while the first was very plain the second has elaborate sculptural decorations on all the columns and door.
This photo shows the four foot thick walls visible only from the entrance to the magazine.
This photo shows the decorated columns, vaulted
ceiling and the wooden wainscoting.