In this picture taken on September 24, 2016, relatives grieve their lost one, an alleged drug user/dealer gunned down by unidentified gunmen in Manila. Philippine President Rodrigo Duterte defended his threat to kill criminals as “perfect” and vowed no let-up in his war on crime, as the death toll surged past 3,700. (Photo by Noel Celis/AFP Photo)

A boy attempts to keep a candle lit in a flooded cemetery following Typhoon Molave, in Masantol, Pampanga, Philippines, October 27, 2020. (Photo by Eloisa Lopez/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.

Paramedics carry an injured woman out from a subway station after a rush-hour subway train derailment, to be transported by a medical helicopter in Moscow, Russia, on Tuesday, July 15, 2014. A rush-hour subway train derailed in Moscow Tuesday, killing 20 people and injuring at least 150, emergency officials said. Several cars left the track in the tunnel after a power surge triggered an alarm, which caused the train to stop abruptly. (Photo by Ivan Sekretarev/AP Photo)

Cristine Angelie Garcia (C), 24, rides a jeepney on her way to work at a call centre for the midnight shift in Taguig city, Metro Manila, Philippines October 3, 2016. “Maybe there is another way where people do not need to die”, she said, adding she felt safer walking the streets at night. “I'm on Duterte's side. Maybe he's just misunderstood because he grew up on the streets”. (Photo by Ezra Acayan/Reuters)

Wounded people walk after clashes with riot police in central Kiev February 18, 2014. Ukrainian riot police advanced on the heart of 12-week-old protests against President Viktor Yanukovich on Tuesday and security forces set a deadline to end disturbances after at least five protesters were reported killed in a day of clashes. (Photo by Vlad Sode/Reuters)

A woman leaves with her television set, as she and others are evicted from their apartment blocks close to the site of last week's building collapse, after their homes were deemed unfit for habitation and marked for demolition, in the Huruma neighborhood of Nairobi, Kenya Friday, May 6, 2016. Following a building collapse which claimed at least 40 lives with more 80 people still unaccounted for, after severe flooding, the government has ordered the demolition of similar unsafe buildings in the area. (Photo by Ben Curtis/AP Photo)