This was while we were following the western pass of the Tidifest Mountains, about the 25th degree of northern latitude.

“I should indeed be ungrateful not to thank you,” I said.

I shall always remember that instant.  We had left our camels and were collecting fragments of the most characteristic rocks.  Morhange employed himself with a discernment which spoke worlds for his knowledge of geology, a science he had often professed complete ignorance of.

Then I asked him the following question: 

“May I prove my gratitude by making you a confession?”

He raised his head and looked at me.

“Well then, I don’t see the practical value of this trip you have undertaken.”

He smiled.

“Why not?  To explore the old caravan route, to demonstrate that a connection has existed from the most ancient times between the Mediterranean world, and the country of the Blacks, that seems nothing in your eyes?  The hope of settling once for all the secular disputes which have divided so many keen minds; d’Anville, Heeren, Berlioux, Quatremere on the one hand,—­on the other Gosselin, Walckenaer, Tissit, Vivien, de saint-Martin; you think that that is devoid of interest?  A plague upon you for being hard to please.”

“I spoke of practical value,” I said.  “You won’t deny that this controversy is only the affair of cabinet geographers and office explorers.”

Morhange kept on smiling.

“Dear friend, don’t wither me.  Deign to recall that your mission was confided to you by the Ministry of War, while I hold mine on behalf of the Ministry of Public Instruction.  A different origin justifies our different aims.  It certainly explains, I readily concede that to you, why what I am in search of has no practical value.”

“You are also authorized by the Ministry of Commerce,” I replied, playing my next card.  “By this chief you are instructed to study the possibility of restoring the old trade route of the ninth century.  But on this point don’t attempt to mislead me; with your knowledge of the history and geography of the Sahara, your mind must have been made up before you left Paris.  The road from Djerid to the Niger is dead, stone dead.  You knew that no important traffic would pass by this route before you undertook to study the possibility of restoring it.”

Morhange looked me full in the face.

“And if that should be so,” he said with the most charming attitude, “if I had before leaving the conviction you say, what do you conclude from that?”

“I should prefer to have you tell me.”

“Simply, my dear boy, that I had less skill than you in finding the pretext for my voyage, that I furnished less good reasons for the true motives that brought me here.”

“A pretext?  I don’t see....”