Some of London's telephone operators and engineers, trying out their gas masks at the anti-gas civilian training centre in Gloucester, where they were taught how to deal with gas attacks. (Photo by Harry Todd/Fox Photos/Getty Images). 13th February 1937

Afghan women learn how to make a doll at a workshop sponsored by a Malaysian NGO called Mercy that seeks to help local females to empower themselves on April 15, 2010 in Kandahar, Afghanistan. (Photo Majid Saeedi/Getty Images)

A caiman swims amidst trash in Canal das Taxas at the Recreio dos Bandeirantes neighborhood in west Rio de Janeiro, Brazil, on November 22, 2023. The urban expansion of the area and the resulting pollution have put the yacare caiman (Caiman latirostris) “in danger of extinction”. (Photo by Tercio Teixeira/AFP Photo)

17-year-old dance student Amelia Hubbard of Halesowen, West Midlands, takes to the park in south Birmingham, United Kingdom on April 14, 2022 to do some spring moves, as temperatures soar in the UK on Good Friday.(Photo by Peter Lopeman/Alamy Live News)

Some women doing yoga pose on the hammocks during the Anti-Gravity yoga class at Svarga e-Motion Sanctuary at Dharmawangsa Square, Jakarta, Saturday, April 18, 2015. Anti-Gravity Yoga or “aerial yoga”, is a new type of yoga, originating in New York but now being practised in several countries, which combines the traditional yoga poses, pilates and dance with the use of a hammock. (Photo by Jurnasyanto Sukarno/JG Photo)

Women take part in an annual block party known as “Banda do Candinho e Mulatas” (Candinho Band and Mulatto Women), during carnival festivities at Bixiga neighbourhood in Sao Paulo, Brazil February 7, 2018. (Photo by Nacho Doce/Reuters)

A young Sandinista guerrilla takes aim with his 45 pistol as he stands waiting to do combat with the Nicaraguan National Guard in Managua June 23, 1979. The guerrillas still occupy major parts of the Capitol City. (Photo by McLendon/AP Photo)

Four-man bicycle is powered by five chains and has brakes on both its wheels, 1948. The bike was built by Art Rothschild (top position) who broke three ribs while learning how to ride it. (Photo by Wallace Kirkland/Time & Life Pictures)