A glass skywalk in Wanyuan, Sichuan province, built along the side of a cliff, is the highest such skywalk anywhere in China on January 31, 2017. Some visitors have been proven to be terrified by the experience had to brace against the wall in fear. (Photo by Chinanew.com/AsiaWire)

A man watches the approaching flames as the Springs fire continues to grow near Camarillo, California, on May 3, 2013. The wildfire has spread to more than 18,000 acres on day two and is 20 percent contained. (Photo by David McNew)

A Palestinian boy carries dates from palm trees during harvest season in southern Gaza September 25, 2016. (Photo by Ibraheem Abu Mustafa/Reuters)

Thierry Reverdi, owner of the Dreamdoll company, adjusts the sunglasses of a silicone dream doll at their workshop in Duppigheim near Strasbourg, December 2, 2014. The realistic silicone s*x dolls can be ordered from a catalogue based on four hair and eye color models for a base price of 5,500 euros ($6,150). The dolls weigh around 40 kilos due to a lightweight aluminum structure and take a week to construct. The company of three employees produces some one hundred custom-made silicone s*x dolls a year, mainly for European customers. (Photo by Vincent Kessler/Reuters)

A three-seater Toyota Kikai concept car is displayed during the 2016 CES trade show in Las Vegas, Nevada January 8, 2016. (Photo by Steve Marcus/Reuters)

Silver medalist Vivian Jepkemoi Cheruiyot of Kenya and gold medalist Almaz Ayana (R) of Ethiopia during the medal ceremony for the women's 10000m final of the Rio 2016 Olympic Games Athletics, Track and Field events at the Olympic Stadium in Rio de Janeiro, Brazil, 12 August 2016. (Photo by Sergei Ilnitsky/EPA)

Two holidaymakers amuse themselves with a porter's trolley whilst waiting for their train at Euston Station, London, 5th August 1939. (Photo by A. J. O'Brien/Fox Photos/Getty Images)

A woman holding an umbrella walks past the sculpture by Chinese artist Yue Minjun beside a road during a snow in Beijing, China, November 22, 2015. (Photo by Jason Lee/Reuters)