At the turn of the 20th century, babies who were born a few months early had little hope of survival. There was no special equipment to keep them warm and no way to feed them.

Some scientists tried to promote the idea of putting the tiny children in boxes that could protect them until they grew strong enough to thrive in a normal environment, but no one seemed to find a way to finance these projects -- until a doctor named Martin Couney had the idea of raising money and promoting the idea at amusement parks, world's fairs and other gathering places.

The plan worked. Visitors paid 10 to 25 cents to look at the babies through a glass partition, and Couney got money to build more incubators to save more lives. The technology is now standard across the world and micropreemies born at 25 weeks gestation and smaller than a pound survive.

The Associated Press interviewed some of the babies who were cared for by Couney in this video:

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