Thurstane knew all this, but he did not say so; for he was a wise, considerate commander already, and he had learned not to chill an informant.  He looked at Coronado inquiringly, as if to say, What do you propose?

“Every canon ought to be explored before we enter it,” continued the Mexican.

“It is a good hint,” said Ralph.  “Suppose I keep two of your cattle-drivers constantly in advance.  You had better instruct them yourself.  Tell them to fire the moment they discover an ambush.  I don’t suppose they will hit anybody, but we want the warning.”

With two horsemen three or four hundred yards to the front, two more an equal distance in the rear, and, when the ground permitted, one on either flank, the train continued its journey.  Every wagon-driver and muleteer had a weapon of some sort always at hand.  The four soldiers marched a few rods in advance, for the ground behind had already been explored, while that ahead might contain enemies.  The precautions were extraordinary; but Thurstane constantly trembled for Clara.  He would have thought a regiment hardly sufficient to guard such a treasure.

“How timorous these men are,” sniffed Aunt Maria, who, having seen no hostile Indians, did not believe there were any.  “And it seems to me that soldiers are more easily scared than anybody else,” she added, casting a depreciating glance at Thurstane, who was reconnoitring the landscape through his field glass.

Clara believed in men, and especially in soldiers, and more particularly in lieutenants.  Accordingly she replied, “I suppose they know the dangers and we don’t.”

“Pshaw!” said Aunt Maria, an argument which carried great weight with her.  “They don’t know half what they claim to.  It is a clever man who knows one-tenth of his own business.” (She was right there.) “They don’t know so much, I verily and solemnly believe, as the women whom they pretend to despise.”

This peaceful and cheering conversation was interrupted by a shot ringing out of a canon which opened into a range of rock some three hundred yards ahead of the caravan.  Immediately on the shot came a yell as of a hundred demons, a furious trampling of the feet of many horses, and a cloud of the Tartars of the American desert.

In advance of the rush flew the two Mexican vedettes, screaming, “Apaches!  Apaches!”

CHAPTER X.

When the Apache tornado burst out of the canon upon the train, Thurstane’s first thought was, “Clara!”

“Get off!” he shouted to her, seizing and holding her startled horse.  “Into the wagon, quick!  Now lie down, both of you.”

He thundered all this out as sternly as if he were commanding troops.  Because he was a man, Clara obeyed him; and notwithstanding he was a man, Mrs. Stanley obeyed him.  Both were so bewildered with surprise and terror as to be in a kind of animal condition of spirit, knowing just enough to submit at once to the impulse of an imperious voice.  The riderless horse, equally frightened and equally subordinate, was hurried to the rear of the leading wagon and handed over to a muleteer.