He tried to thrust his thumbs into Frank's eyes.
"I'll kill you, if you don't let me go!" he snarled.
Frank had felt from the first that his assailant could not be Buck Badger; now he recognized the voice of Donald Pike, for Pike, in his fright and desperation, forgot to keep up the disguise.
Seeing that the only way to deal with Pike was to choke him into semi-insensibility, he caught and crushed down the flailing fists and arms and tightened his grip on Pike's throat.

Pike writhed and flounced, kicking and struggling, but all without avail.

That viselike grip grew tighter and tighter.

The pain seemed unbearable.

He gurgled and choked, and his lungs seemed to be bursting.