(WTRF) — In the mid-twentieth century, many polio patients with breathing issues were placed inside a long metal tube called an iron lung.

The machine regulated air pressure and helped stimulate breathing, says CNN.

A Texas man is one of the last remaining people still using an iron lung, reports say.

Paul Alexander, has been inside an iron lung for 70 years, beginning in 1952 when be contracted polio at age 6. The disease left him paralyzed from the neck down, say reports.

A therapist promised the young Alexander a dog if he could breathe on his own for a few minutes, and he developed a way to hold air in his lungs for hours. This accomplishment enabled him to leave the machine for hours at a time.

Alexander completed college and law school and worked as a courtroom attorney for 30 years. He even wrote an autobiography, say reports.