Antique safes evolved from the earlier iron boxes around 1820. Safes were essential pieces of office equipment, designed to protect against both fire and burglary. Safes did not do a very good job against fire until design improvements after 1840. From that time, Diebold and other manufacturers also began to create and install combination locks that ensured the protection of papers and valuables under almost all conditions. The opener of the antique safe must either know the lock combination or be able to circumvent the lock.
Turn the dial of the combination lock slowly to the right. Listen, and feel, for any slight click. Stop immediately at the point of the click. Write down the number.
Turn the dial carefully to the left. Listen, and feel, for a click. Stop, and write down the number.
Rotate the dial back to the right. Stop at the first click. Write down the number.
Pull the handle on the door of the antique safe. If the door does not open, try turning the dial again and listening, and feeling, for clicks. Do not repeat any of the combinations you have already tried.
If none of the combinations work, drill into the safe near the axis of the combination lock dial. Most antique safes are guarded by thick plates of iron or steel. Drilling will be difficult, and take a long time. Drill until the inner workings of the combination lock are visible.
Turn the combination lock dial until the lock gates are positioned to cause the lock fence to fall. The lock gates hold the lock fence, or fence lever, in place. When the lock fence falls, it will release the bolt and open the lock.