its own machines, hangars and repair-shop, and he flies where he likes.
Look at 'em!"

They crowded out with whatever glasses they could lay their hands upon
and watched the two tiny machines that circled and dipped, climbed and
banked about one another.

* * * * *

First one would dart away with the other in pursuit, then the chaser, as
though despairing of overtaking his quarry, would turn back. The "hare"
would then turn and chase the other.

"Have you ever seen two puppies at play?" asked Blackie. "Look at Tam
chasing his tail--and neither man knows the other or has ever looked
upon his face! Isn't it weird? That's von Hansen-Bassermann's ninth
sense. They can't speak--they can't even see one another properly and
yet they're good pals--look at 'em. I've watched the puppies of the pack
go on in exactly the same way."

"What is Tam supposed to be doing?"

"He's watching the spotters. Tam will be down presently and we'll ask
David how he came to meet Jonathan--this business has been going on for
weeks."

Tam had received the recall signal. Beneath him he saw the two
"spotters" returning home, and he waved his hand to his sporting
companion and came round in a little more than twice his own length. He
saw his strange friend's hand raised in acknowledgment, and watched him
turn for the south. Tam drove on for a mile, then something made him
look back.

Above his friend was a glittering white dragon-fly, and as he looked the
fly darted down at the American tail.

"Missed him!" said Tam, and swung round. He was racing with the wind at
top speed and he must have been doing one hundred and twenty miles an
hour, but for the fact that he was climbing at the extreme angle. He saw
the dragon-fly loop and climb and the American swing about to attack.

But his machine was too slow--that Tam knew. Nothing short of a miracle
could save the lower machine, for the enemy had again reached the
higher position. So engrossed was he with his plan that he did not see
Tam until the Scot was driving blindly to meet him--until the first
shower from Tam's Lewis gun rained on wing and fuselage. The German
swerved in his drive and missed his proper prey. Tam was behind him and
above him, but in no position to attack. He could, and did fire a drum
into the fleeing foeman, but none of the shots took effect.

"Tairn him, Archie!" groaned Tam, and as though the earth gunners had
heard his plea, a screen o