"Quite so, and thus it happens that in the absence of children of the Grand Duke Rudolph, your future pupil, Duke Joachim, son of the Grand Duke Frederick and some German countess, is now the heir presumptive to the State of Lautenburg-Detmold. To alter the situation the marriage of his father with the Grand Duchess Aurora would have to be honoured with a bond, a thing which seems most improbable." "I seem to remember something about it now," I said. "Wasn't there a German Grand Duke who died in Africa--the Congo--while engaged in geographical research two or three years ago?" "Precisely," replied M. Thierry. "That was the Grand Duke Rudolph. He was always an enthusiastic geographer. His travels could not, it is true, be described as altogether unpolitical. When I remember that a few months later we had Agadir and the loss of the Congo, I can't help thinking that the Grand Duke of Lautenburg had been sent to accomplish some mission on behalf of his august cousin, the Kaiser. It is true he hadn't much time in which to effect his purpose as he died in the Congo shortly after his arrival. It would be interesting...." "But what is there in all this, sir," I broke in, "that in any way accounts for the solicitude you've just shown on my behalf?" He seemed put out. "My dear boy," he said, with an obvious effort. "A historian's plain duty is to accept as fact only what he has been able to verify. From that point of view I confess that my knowledge is confined to vague rumours barely susceptible of proof. Certain reports, an allusion or two, and last--but not least--certain details communicated to me some time back by a friend whose name I must withhold--that's all. I should perhaps add the proverb that there is no smoke without fire." "Couldn't you be a little more precise as to the purport of the rumours?" "Will you promise you will keep this entirely to yourself?" he said. "I give you my word." "I am told that violent deaths are not unknown at the Court of Lautenburg-Detmold." My curiosity reached fever-heat. "What does that mean?" I asked. "Unfortunately, or rather, fortunately, nothing definite. Still, we can't ignore the fact that two persons stood between Duke Frederick Augustus and the crown." "But the Grand Duke Rudolph died of sunstroke in the Congo," I said. "It was reported in the press." "Agreed. That was a natural death all right, but apparently the same cannot be said of the death of Countess von Tepwitz--the present Duke's first wife and the mother of Duke Joachim." "Do you mean that the Grand Duke was responsible for her death?"