On Saturday night a homemade bomb detonated on the sidewalk in Manhattan's Chelsea district, injuring 29 passersby. Investigating police subsequently located a second bomb just four blocks away. Consisting of a pressure cooker connected to a cell phone that served as a timer, and presumably filled with the same ball bearings that served as shrapnel in the first bomb, it had not been detonated.

In the movies I grew up with, a brave, heavily perspiring cop would kneel next to this and disarm it with handheld wirecutters. In real life the procedure is more prosaic: Bomb technicians use a robot to pick the bomb up, then stuff it into what's called a Total Containment Vessel, or TCV. Here's a photo, captured by the New York Times' Sandra E. Garcia, of the bomb being taken away in a TCV:

The attendant Times article refers to the TCV as "an inside-out diving vessel." In the event of a detonation, the spherical chamber is designed to contain blasts and shrapnel, while simultaneously allowing pressure to escape via tiny vents. Up close, they look like the offspring of a cement mixer and a front-loading washing machine:

That TCV belongs to the Tennessee Highway Patrol. As fears of terrorism have spread across the country, so too have the TCVs. Manufacturer NABCO—self-described as "the world leader in the design, development and manufacture of explosive and chemical, biological, radiological and nuclear (CBRN) containment mitigation systems"—calls TCVs "the first choice of EOD and Bomb Squads worldwide."

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Earlier on Saturday, a bomb left along the route of a charity race in Seaside Park, New Jersey, was detonated. (No injuries were reported.) And just this morning, a backpack containing "as many as five potential explosive devices" was found in a trash can in Elizabeth, New Jersey. Apparently lacking a TCV, police there used a robot to attempt to disarm one of the bombs on-site, and here's what happened (Warning, turn your speakers down):

That was one of the five bombs detonating. Thanks to the use of the robot no one was injured, though it does highlight the peril of attempting to disarm devices like these on-site.

Many of us have never seen a TCV in person. But as events like these continue to increase, it's likely we eventually will.