Finally carbon dioxide builds up in the lungs and in the blood stream, and the cramps partially subside. Spasmodically he is able to push himself upward to exhale and bring in life-giving oxygen.
Hours of this limitless pain, cycles of twisting, joint-rending cramps, intermittent partial asphyxiation, searing pain as tissue is torn from his lacerated back as he moves up and down against the rough timber. ...