mode of
conveyance.

"Ay, lad, and they'd need to be stout timbers too, to make headway
through such a sea of sand," returned Molloy, feeling his own limbs with
tenderness. "D'ee think we're in for a brush to-night, lad?"

Before the latter could reply, an aide-de-camp ran up and spoke a few
hurried words to Captain Lacey, who turned to his company and called
them to attention.

"Fours, right--quick march!" he said, and away they went, past the flank
of Hudson's men, to guard a hollow which left that part of the square
somewhat exposed. When halted and drawn up in line several files were
thrown out in advance. Miles and Sutherland formed the flanking file on
the right, the latter being rear-rank man to the former.

"It's a grand hiding-hole," observed Sutherland, as he peered cautiously
over the edge of a low bank into a hollow where rocks and undergrowth
were thickly intermingled.

"Keep a sharp look-out on your left, Sutherland," said Miles, "I will
guard the right--"

He stopped abruptly and threw forward his rifle, for at that moment he
observed a swarthy, black-bearded Arab, of large proportions and
muscular frame, creeping forward a short distance below him. Evidently
he had not heard or seen the approach of the two soldiers, for he was
gazing in a different direction from them.

Miles raised his rifle and took aim at the man, but he felt an
unconquerable repugnance to shoot. He had never yet met the enemy
hand-to-hand. His experience heretofore had been confined to long-range
firing at men who were firing at himself and his comrades, and in which,
of course, he could not be sure that his bullets took effect. But now
he was within fifty yards of a splendid-looking man who did not see him,
who was, at the moment, innocent of any intention of injuring him, and
whose expressive side-face he could clearly distinguish as he crept
along with great caution towards a rock which hid the zereba of the
Europeans from his view.

Miles was a good rifle-shot. A touch of the trigger he knew would be
certain death to the Arab.

"I _cannot_ do it!" he muttered, as he lowered his weapon and looked
back over his shoulder at his comrade. The Scot, who was something of a
naturalist, was engrossed at the moment in the contemplation of a little
bird which was twittering on a twig in quite an opposite direction.

Miles glanced again at the Arab in a flutter of agitation as to what was
his duty. The man _might_ be