Stratospheric cool

Early in the 20th century, as test pilots began flying higher than Mount Everest, they had to defend themselves against temperatures as low as minus-80 degrees Fahrenheit. To survive the frigid blast, they wore leather hoods, and they insulated their eyes with fur-lined goggles. To lift those goggles for even an instant was to risk death. In 1920, when Shorty Schroeder dared to take a biplane above 33,000 feet, his goggles fogged and he had no choice but to pull them off. Moments later, his vision blurred, and his eyes were soon frozen over. Schroeder managed to land the plane that day, and his friend John Macready helped pull him out of the cockpit. A month later, still haunted by the memory of his friend’s swollen eyelids, Macready climbed into the same plane to beat Schroeder’s altitude record. Like Schroeder, Macready depended on goggles that had been designed to seal his eyes from the cold and protect his sight. But the early goggles were not dark enough, and “the bright sunlight in the upper atmosphere hurt his eyes,” said his daughter, Sally Macready Wallace. And so Macready began working with X to design goggles especially suited to protect against the dazzle in the stratosphere. “My dad gave X the original ____” of Y, Wallace said. By the late 1930s advertisements for X's Z brand of Y started coming out. Identify X Y Z