both know where the salt spring is, Tom, so I will take the paper
there, and you go to some place where you can watch the spring through
your field-glasses," said the Doctor.

"Very good. By the time we get a reply Burton may be back," said Tom,
and they left the camp.

Tom watched patiently all day, but, with the exception of a boy in
charge of some goats, no one went near the spring, and the boy did not
go within a hundred yards of it, though his goats were feeding all round
and close to it.

"Glad to see you back, Burton," exclaimed Tom when he returned to camp
and found the officer there.

"What luck, Tom?" asked the Doctor.

"Bad. I waited until it was too dark to see, and the message had not
been taken when I came away," he replied.

"You are wrong, Tom, my boy, for I saw it taken," said Burton.

"How? Where were you?" asked Tom, in surprise.

"Not far from you, and I saw a goat sniff it and quickly walk off with
the paper in its mouth, and five minutes later the boy had it in his
hand. Here, smell this," and Burton held out the paper containing the
message to the Doctor.

"A peculiar smell," said Tom.

"Yes, and the goat is trained to carry anything impregnated with that
subtle odour," explained Burton.

"Do you believe the writer of this knows where Mark is, Burton? Have you
discovered anything?" asked Tom.

"Yes, the man knows well enough, and I know to half a mile," said
Burton.

"They why not try to release him at once?" exclaimed Tom.

"Easier said than done, and I am fully convinced it would be dangerous
to force matters without careful arrangements. I practically know with
whom we have to deal, and, if I am any judge of native character, I
believe we are in conflict with some of the most cunning and fearless
men in India--men who had been carrying on their work for many years,
and that, too, without raising suspicion, and who will not hesitate to
risk life and cause death to accomplish their purpose, and----" Burton
suddenly stopped speaking; then, almost in a whisper, he hurriedly said,
"Go on talking about Mark," and noiselessly he left the tent.

In a few moments there was a sound of a scuffle at the back of the tent,
followed by a thud and an exclamation from Burton; so they rushed out to
see what had happened, the Doctor taking the lamp from the tent-pole as
he passed.

"What's the matter, Burton?" asked Tom.

"Bring the lamp here," he answered, rubbing his knees. "They were too