An ugly growl from Chum punctuated his scared plea. Noting the
terror in his master's tone and the grip of the stranger on
Link's arm, Chum had spun round to face the two.

The collie's eyes were fixed grimly upon the plainclothes man's
temptingly thick throat. One corner of Chum's upper lip was
curled back, displaying a businesslike if snowy fang. His head
was lowered. Deep in his furry throat a succession of legato
growls were born.

The plain-clothes man knew much about dogs. He knew, for example,
that when a dog holds his head high and barks there is no special
danger to be feared from him. But he also knew that when a dog
lowers his head and growls, showing his eyetooth, he means
business.

And the man shrank from the menace. One hand crept back
instinctively toward his hip pocket.

Link saw the purely involuntary gesture, and he shook in his
boots. It was thus a Hampton constable had once reached back when
a stray cur snapped at him. And that constable had completed the
movement by drawing a pistol and shooting the cur. Perhaps this
non-uniformed stranger meant to do the same thing.

"Hold on!" begged Link, intervening between the man and the dog.
"I'll go along with you peaceful. Quit, Chum! It's all right!"

The dog still looked undecided. He did not like this new note in