In the 1960s, National Geographic photographer Bates Littlehales invented a device that enabled wide-angle photography underwater. Called OceanEye, it's a Plexiglas contraption with handles and controls that link to the camera inside of it. Here's what it looks like:
Today another National Geographic photographer, David Doubilet, uses OceanEye to capture shots that are half-in, half-out of the water. The stunning images are collected in Two Worlds: Above and Below the Sea, published by Phaidon.