The Lone Wolf by Louis Joseph Vance

It was late afternoon when Lanyard wakened from sleep so deep and dreamless that nothing could have induced it less potent than sheer systemic exhaustion, at once nervous, muscular and mental.

A profound and stifling lethargy benumbed his senses. There was stupor in his brain, and all his limbs ached dully. He opened dazed eyes upon blank darkness. In his ears a vast silence pulsed.