A mudlark uses a torch to look for items on the bank of the River Thames in London, Britain June 06, 2016. Mudlarking is believed to trace its origins to the 18th and 19th century, when scavengers searched the Thames' shores for items to sell. These days, history and archaeology fans are the ones hoping to find old relics such as coins, ceramics, artifacts or everyday items from across centuries. their finds with the Portable Antiquities Scheme. Any item over 300 years old must be recorded. (Photo by Neil Hall/Reuters)

A man poses in front of a portrait of late Chinese Chairman Mao Zedong during the opening of an exhibition of Mao related art in Beijing, China, September 8, 2016. (Photo by Thomas Peter/Reuters)

Labrador puppies “Hoey” (L) and “Hatton”, named in honor of September 11, 2001 attack victims Patrick Hoey and Lenny Hatton who died in the World Trade Center, are pictured on the grounds of the Pentagon near Washington, June 28, 2011. (Photo by Jason Reed/Reuters)

A vendor sells chili peppers at his stall at a market in Bangkok, Thailand March 31, 2016. (Photo by Jorge Silva/Reuters)

A woman photographs a Norwegian spruce Christmas tree from Oslo after it was lit at Trafalgar Square in central London, December 4, 2014. (Photo by Toby Melville/Reuters)

People take pictures and Buddhist monk chants as a groom and a bride lay inside a pink coffin during their wedding ceremony at Wat Takien temple in Nonthaburi province, on the outskirts of Bangkok February 14, 2015. Ten Thai couples laid in the pink coffin starting 9:09 AM on Saturday during the wedding ceremony organised by the Buddhist temple on Valentine's Day. Couples believe laying briefly in the coffin will get rid of bad luck and usher happiness into their lives. (Photo by Damir Sagolj/Reuters)

An original 1850 puntabout rugby football is displayed at Rugby School in central England, March 18, 2015. Rugby School is known as the spiritual home of rugby. According to a popular version of the game's origins, it was on the school's playing field that in 1823, in a game that could loosely be described as football but was more like a brawl, a pupil called William Webb Ellis caught the ball and, instead of kicking towards the goal, sprinted with it – breaking the code and laying the way for modern-day rugby. (Photo by Neil Hall/Reuters)

Students stand on the roof of a wooden boat as haze blankets the Musi River while they travel to school in Palembang, on Indonesia's Sumatra island, September 10, 2015. Indonesia is investigating 10 firms over worsening forest fires that have created a blanket of smog over Southeast Asia, threatening them with sanctions if they are found responsible, a government minister said on Tuesday. The thick haze from Indonesia's Sumatra and Kalimantan islands has forced the repeated cancellation of flights in the area and pushed air quality to unhealthy levels in neighbouring Singapore and Malaysia. (Photo by Reuters/Beawiharta)