With that he drew his dagger and cut open a locked pouch which had dangled from the thern's harness, and from it he brought forth a circlet of gold set with a large gem—it was the mate to that which I had taken from Sator Throg.
"He was a Holy Thern," said Xodar. "Fortunate indeed it is for us that he did not escape."
The officer of the guard entered the chamber at this juncture.
"My Prince," he said, "I have to report that this fellow's companion escaped us. I think that it was with the connivance of one or more of the men at the gate. I have ordered them all under arrest."
Xodar handed him the thoat oil and cloth.
"With this you may discover the spy among you," he said.
I at once ordered a secret search within the city, for every Martian noble maintains a secret service of his own.
A half-hour later the officer of the guard came again to report. This time it was to confirm our worst fears—half the guards at the gate that night had been therns disguised as red men.
"Come!" I cried. "We must lose no time. On to Hastor at once. Should the therns attempt to check us at the southern verge of the ice cap it may result in the wrecking of all our plans and the total destruction of the expedition."
Ten minutes later we were speeding through the night toward Hastor, prepared to strike the first blow for the preservation of Dejah Thoris.