The dipping sound came nearer and presently there slipped from the shadow of the trees a darker shadow, moving.  A canoe with one paddle was coming toward them.

Esther with undignified haste scrambled up from the float, abandoning her position in the line of battle in favour of the doctor.  The dog broke into a chorus of ear-splitting yelps of warning and welcome.  The moving shadow loomed larger and a calm though harsh voice demanded, “Be quiet, General!  Who is there?”

“We are!” answered Callandar, stepping as far from the tree shadow as possible.  “Picnickers from Coombe, in an unfortunate predicament.  Our motor has broken down, and we want the loan of a boat to get over to Pine Lake station.”

As he spoke he was vividly conscious of Esther close behind.  So near was she that he felt her warm breath on his neck.  She was breathing quickly.  Was the child really frightened?  Instinctively he put out his hand, backward, and thrilled through every nerve when something cool and small and tremulous slipped into it.

The canoe shot up to the float.

“You can’t get any boat here.”

There was no surprise or resentment in the harsh level voice.  Only determination, final and unshakable.

Esther felt the doctor’s hand close around her own.  Its clasp meant everything, reassurance, protection, strength.  In the darkness she exulted and even ventured to frown belligerently in the direction of the disagreeable canoeist.  They could see her plainly now.  A tall woman in a man’s coat with the sleeves rolled up displaying muscular arms.  Her face, even in the half-light, looked harsh and gaunt.  With a skill, which spoke of long practice, she sprang from the canoe, scarcely rocking it, and proceeded to tie the painter securely to a heavy ring in the float.  Then she straightened herself and turned.

“I’ll loose the dog!” she announced calmly.

Just that and no more!  No arguments, no revilings, no display of any human quality.  There was something uncanny in her ruthlessness.

“If you do, it will be bad for the dog,” said Callandar coldly.  “Who are you who threaten decent people?”

It was the tone of authority and for an instant she answered to it.  Her harsh voice held a faint Scotch accent.

“There’ll be no decent people here at this hour o’ the nicht.  Be off.  You’ll get no boat.  Nor the hussy either.  The dog’s well used to guarding it.”

“How dare you!” Esther was so angry at being called a hussy that she forgot how frightened she was and faced the woman boldly.  But the old hard eyes stared straight into her young indignant ones and showed no softening.  Next moment old Prue had pushed the girl aside and disappeared in the darkness of the wooded path.

“Quick!” The doctor’s tone was crisp and steady.  “The canoe is our chance.  Jump in, while I hold it—­in the bow, anywhere!”

“But the paddle!  She has taken the paddle!” Even as she objected she obeyed.  The frail craft rocked as she slid into it, careful only not to overbalance; next moment it rocked more dangerously and then settled evenly into the water under the doctor’s added weight.