"Mr Purchase," he said, "I have been trying to put two and two together--or, in other words, I have been endeavouring to find an explanation of the puzzle which this business of the wreck of the _Psyche_ presents.  I can understand quite clearly that poor Captain Harrison was deliberately deceived and misled by certain persons in Sierra Leone in order that the ship might be cast away.  But why _here_ particularly?  For if my theory be correct that the supposed decoy schooner actually sailed out of this river with a full cargo of black ivory, there must certainly be a barracoon somewhere close at hand from which she drew her supplies; and the people who planned the destruction of the sloop could scarcely have been so short-sighted as to have overlooked the fact that such a happening would leave us here stranded in close proximity to a slave factory which, presumably, they would be most anxious should remain undiscovered by us.  That is the point which I cannot understand; and I have come to the conclusion that my theory with regard to the schooner must be altogether wrong, or there must be something else in the wind--that, in short, the wreck of the sloop is only a part instead of the whole of their plan."