A gilrl plays games in a shopping mall in Beijing, China, 24 November 2021. Demographers in China have called for more efficient implementation of supportive measures to encourage births to address the country's dwindling population growth as country's birthrate last year was 8.52 births per thousand people, the lowest level since 1978, according China Statistical Yearbook 2021. (Photo by Wu Hong/EPA/EFE)

A honour guard soldier gives a flower to a girl on International Women's Day in St. Petersburg, Russia, Friday, March 8, 2024. International Women's Day on March 8 is an official holiday in Russia. Per tradition, men give flowers and gifts to female relatives, friends and colleagues, even though in the past two years flowers have gotten more expensive. Marches, demonstrations and conferences are being held the world over, from Asia to Latin America and elsewhere. (Photo by Dmitri Lovetsky/AP Photo)

People wearing masks and carrying supplies walk past a mannequin wearing a mask in downtown Barcelona, Spain, Saturday, March 14, 2020. Spain's prime minister has announced a two-week state of emergency from Saturday in a bid to contain the new coronavirus outbreak. For most people, the new coronavirus causes only mild or moderate symptoms. For some, it can cause more severe illness, especially in older adults and people with existing health problems. (Photo by Emilio Morenatti/AP Photo)

A demonstrator reacts during a rally following the death in Minneapolis police custody of George Floyd, in Boston, Massachusetts, U.S., June 2, 2020. (Photo by Brian Snyder/Reuters)

People react following the verdict in the trial of former Minneapolis police officer Derek Chauvin, found guilty of the death of George Floyd, at BLM Plaza in Washington, D.C., U.S., April 20, 2021. (Photo by Evelyn Hockstein/Reuters)

A Syrian refugee girl plays outside a tent at a refugee camp in Zahle in the Bekaa valley November 18, 2014. In October, Lebanon, which has the highest per capita concentration of refugees in the world at one in four residents, said it could not cope with more than one million Syrians and has asked for funds to help look after them. (Photo by Mohamed Azakir/Reuters)

A instructor (2nd L) from the Philippine Mermaid Swimming Academy assists participants of a monofin swimming summer workshop as they practise floating in the water of a private pool in Paranaque city, metro Manila April 5, 2014. The Philippine Mermaid Swimming Academy workshops, which were originally conducted on the beaches of Boracay Island, central Philippines, currently cost 1,800 pesos per person ($40) for a two-hour session. (Photo by Romeo Ranoco/Reuters)

Jacob's Well is a perennial karstic spring in the Texas Hill Country flowing from the bed of Cypress Creek, located northwest of Wimberley, Texas. The twelve foot (four meter) diameter mouth of the spring serves as a popular swimming spot for the local land owners whose properties adjoin Cypress Creek. From the opening in the creek bed, Jacob's Well cave descends vertically for about thirty feet (ten meters), then continues downward at an angle through a series of silted chambers separated by narrow restrictions, finally reaching a depth of one hundred and twenty feet (forty meters). Until the modern era, the Trinity Aquifer-fed natural artesian spring gushed water from the mouth of the cave, with a measured flow in 1924 of one hundred and seventy gallons per second (six hundred and forty liters per second) discharging six feet (two meters) into the air. The spring is the greatest source of water recharging the Edwards Aquifer.