He was now riding so fast that he could soon have overtaken the animals, in spite of the upward gradient. But if he did so, he would either run the risk of coming into collision with one of them, or drive them over the edge of the track on the left, and down the somewhat steep and dangerous slope to the river. It occurred to him that he might do better to moderate his pace and keep fairly close on their heels. They might prove useful. The cross-track to which he would come presently was somewhat looser than that on which he was riding. If the enemy happened to be at the cross-roads beyond, the horses and the dust they raised might serve him as a temporary screen. So he opened his air throttle a little, and closed the petrol throttle to the same extent, maintaining a speed that would keep the horses on the run without exposing him to the risk of being overtaken.
He soon found that there was a certain disadvantage in following upon the heels of the horses. On coming into the cross-track, he was enveloped in a cloud of dust, thick enough to prevent his seeing more than a few yards ahead. The dust and the bodies of the animals completely shut out the view, and he realised that as he neared the fork he would be quite unable to tell what awaited him there. He thought it advisable to drop a little behind. No doubt the horses would turn to the left when they reached the crossroads, and gallop towards the Inca camp--the place which for some days past they had associated with fodder. If the enemy had not actually passed the fork and marched down the eastern track, he might manage to turn into it unperceived under cover of the dust-cloud, and soon ride out of danger.
Slackening down until he had doubled his distance from the horses, he noticed on his right hand a belt of trees which, if his memory was not at fault, extended for nearly a mile along the southern edge of the cross-track until it joined the eastern path. With one eye on the horses and the other on the trees he watched for the branching of the tracks. It came sooner than he expected. Suddenly the horses swerved to the left; a few seconds afterwards he turned to the right, and felt the machine quicken under him on the downward incline.
At that instant he heard the loud crackle of rifles behind him. Posted among the trees just above the fork there was a body of men who, watching with astonishment the maddened gallop of three riderless horses, caught a faint glimpse of the motor-cycle as it emerged from the whirling dust. They fired too hurriedly to hit the mark. At the sound of the shots Tim bent double and let the machine go. Riding at the rate of thirty miles an hour he knew that the enemy could not catch him on horseback on this particular portion of the track. But when he came to the foot of the hill, and began to climb a long rise, he glanced round and saw a large troop of horsemen dashing down in pursuit. They were a long way behind, and unless some accident befell the machine, he was sure that he could outpace them with ease.
The track wound frequently. For long stretches he was hidden from the pursuers. Looking back now and then he noticed with satisfaction, whenever they came in sight, that he was steadily increasing the interval between him and them. He might have run away altogether if he had driven the machine at full speed; but the track was very rough, and he felt that he must watch it carefully if he was to avoid the risk of a second puncture, or of collision with some boulder. Downhill he often had to check his pace, and so could not take full advantage of the descents to give him impetus for the upward gradients of the switchback. But as mile after mile was covered he became less and less fearful of being caught; and when, at the end of a long, straight stretch, he saw that the enemy were at least two miles behind, he was perfectly easy in mind, and only wondered why they had not given up the hopeless chase.
His former journeys on this track had made him pretty familiar with the landmarks, and as he rode up a long incline, he knew that he would soon be in sight of the wooden bridge over the ravine, beyond which the party of Japanese were posted. A few miles of switchback, and then he would have a downward run home. But on rising slowly over the crest, he was staggered to see a troop of some twenty horsemen halted no more than half a mile in front of him. The track dipped to within about a hundred yards of the spot where they were standing, then bent somewhat sharply upwards, and disappeared over the brow rather more than half a mile ahead.
Tim instantly realised the desperate position into which he had come unawares. His first impulse was to screw on his brakes and dismount, to avoid rushing headlong among the enemy. But in a flash he saw that to do so would be simply to give himself into their hands, or into the hands of the men behind him. There was no escape either on the right or the left. The only possible course was to ride on and take his chance. Setting his teeth, and crouching almost flat over the handle-bar, he opened the throttle, and shot down the hill, sounding his hooter violently all the way.
If he had had the leisure to calculate the possible result he could scarcely have anticipated the success of his action. The horsemen instinctively edged away to the sides of the track, and on to the edge of the rough moorland which bounded it on the east. Some had the presence of mind to whip out their pistols, but as the cycle raced towards them with ever-quickening speed they found themselves in trouble with their horses, which began to quiver and sweat and prance at the strange sight and the terrifying sounds. Down flew the cycle, Tim gripping the handle-bar hard, no longer able to pick his course, but keeping the middle of the track, rough or smooth. He was unconscious of jerks and jolts; blind to the risk of puncture; in that critical half-minute he thought of nothing but the task of steering so as to avoid collision with the enemy, a disaster which they on their part were no less anxious to escape.
He was upon them, in a whirl of dust raised by the wind of his flight. A thrill shot through every fibre as he skimmed danger by a hair's breadth. One of the horses was cavorting on his hind legs, and his rider, almost as frantic as the animal, turned him into a whirligig by hard tugging at the bridle. A few shots were fired by the other troopers, but no man could take steady aim from the back of a rearing horse, at an object flashing by at forty miles an hour. With a rush and a whizz Tim was past.
But his momentary joy at having got through vanished as he felt the slackening of speed enforced by the steep incline beyond. On his former journey he had dismounted and wheeled the machine. There was a great hubbub behind him. The throbbing hum of his engine was smothered by the clatter of the horses' hoofs, and the yells of their riders spurring them on. Short as the ascent was, its angle was so sharp as to neutralise in great measure the impetus he had gained downhill. Moment by moment the machine flagged, and, without looking behind, he was conscious that the pursuers were gaining. He feared that his engine power would not suffice to bring him to the top, upon which he fixed his eyes as it were imploringly. How far away it seemed!