Two officers who are in command of a convict-guard learn an important secret as to buried treasure.

A map is drawn for them by an Englishman named Jonathan Small.

You remember that we saw the name upon the chart in Captain Morstan's possession.

He had signed it in behalf of himself and his associates,--the sign of the four, as he somewhat dramatically called it.

Aided by this chart, the officers--or one of them--gets the treasure and brings it to England, leaving, we will suppose, some condition under which he received it unfulfilled.