"Instructions to Lord John Roxton and party.
To be opened at Manaos upon July 15th, at 12 o'clock precisely."
Lord John had placed his watch upon the table beside him.
"We have seven more minutes," said he.
"The old dear is very precise."
Professor Summerlee gave an acid smile as he picked up the envelope in his gaunt hand.
"What can it possibly matter whether we open it now or in seven minutes?" said he.
"It is all part and parcel of the same system of quackery and nonsense, for which I regret to say that the writer is notorious."
"Oh, come, we must play the game accordin' to rules," said Lord John.
"It's old man Challenger's show and we are here by his good will, so it would be rotten bad form if we didn't follow his instructions to the letter."
"A pretty business it is!" cried the Professor, bitterly.
"It struck me as preposterous in London, but I'm bound to say that it seems even more so upon closer acquaintance.
I don't know what is inside this envelope, but, unless it is something pretty definite, I shall be much tempted to take the next down-river boat and catch the Bolivia at Para.
After all, I have some more responsible work in the world than to run about disproving the assertions of a lunatic.
Now, Roxton, surely it is time."
"Time it is," said Lord John.
"You can blow the whistle."
He took up the envelope and cut it with his penknife. From it he drew a folded sheet of paper. This he carefully opened out and flattened on the table.
It was a blank sheet.
He turned it over.
Again it was blank.
We looked at each other in a bewildered silence, which was broken by a discordant burst of derisive laughter from Professor Summerlee.
"It is an open admission," he cried.
"What more do you want?
The fellow is a self-confessed humbug.
We have only to return home and report him as the brazen imposter that he is."
"Invisible ink!" I suggested.
"I don't think!" said Lord Roxton, holding the paper to the light.
"No, young fellah my lad, there is no use deceiving yourself.
I'll go bail for it that nothing has ever been written upon this paper."
"May I come in?" boomed a voice from the veranda.
The shadow of a squat figure had stolen across the patch of sunlight.
That monstrous breadth of shoulder!
We sprang to our feet with a gasp of astonishment as Challenger, in a round, boyish straw-hat with a colored ribbon—Challenger, with his hands in his jacket-pockets and his canvas shoes daintily pointing as he walked—appeared in the open space before us.
He threw back his head, and there he stood in the golden glow with all his old Assyrian luxuriance of beard, all his native insolence of drooping eyelids and intolerant eyes.
"I fear," said he, taking out his watch, "that I am a few minutes too late.
When I gave you this envelope I must confess that I had never intended that you should open it, for it had been my fixed intention to be with you before the hour.
The unfortunate delay can be apportioned between a blundering pilot and an intrusive sandbank.
I fear that it has given my colleague, Professor Summerlee, occasion to blaspheme."
"I am bound to say, sir," said Lord John, with some sternness of voice, "that your turning up is a considerable relief to us, for our mission seemed to have come to a premature end.
Even now I can't for the life of me understand why you should have worked it in so extraordinary a manner."
Instead of answering, Professor Challenger entered, shook hands with myself and Lord John, bowed with ponderous insolence to Professor Summerlee, and sank back into a basket-chair, which creaked and swayed beneath his weight.
"Is all ready for your journey?" he asked.
"We can start to-morrow."
"Then so you shall.
You need no chart of directions now, since you will have the inestimable advantage of my own guidance.
From the first I had determined that I would myself preside over your investigation. The most elaborate charts would, as you will readily admit, be a poor substitute for my own intelligence and advice.
As to the small ruse which I played upon you in the matter of the envelope, it is clear that, had I told you all my intentions, I should have been forced to resist unwelcome pressure to travel out with you."
"Not from me, sir!" exclaimed Professor Summerlee, heartily.