THE ANSWER TO LAST WEEK’S MYSTERY

ATLANTA, Texas — Railroad trains used to conclude with an interesting final car — the caboose. No longer.

Now the train ends with a FRED, a flashing rear-end device.

The FRED is a small, portable metal box with a flashing light located on the rear of the last car. One hardly notices it. But they are smart just like a cell-phone and can do a number of tasks that the caboose once made possible.

Starting with the caboose, here are some jobs it participated in:

■ It was the facility where the conductor did his paperwork.

■ On long routes the caboose was a place for accommodation and cooking facilities.

■ As a shelter, the crew could observe the train from here.

■ From here the crew could exit for switching or to protect the rear of the train when stopped.

The crew had to be fairly mobile.

They had to inspect the train for problems such as shifting loads, dragging equipment and overheated bearings called hot boxes.

Over time, some of these problems were solved, such as when bearings were improved.

Line-side detectors detected hot boxes and better-designed care methods avoided load-shifting. The caboose even became a dangerous place when slack run-ins could hurl the crew from their places.

A popular model caboose — such as the Atlanta Chamber of Commerce has at its office, which used to be the train depot, — is called a cupola model.

The cupola would be the small projection on the roof with windows where the crew could sit in elevated seats to inspect the train from this perch.

The FRED now detects all air brake pressure, reports movement of the train upon start-up and radios this to the engineer, so he knows all slack is out of the couplings and more power can be applied.

Also, the blinking light warns people that a train is present.

Cabooses were used on every freight train in the U.S. until the 1980s when safety laws requiring the presence of cabooses and full crews were relaxed.

When the FREDs came, the conductor moved up to the front of the train with the engineer.

Staff photo by Neil Abeles ■ The flashing white, twin lights at the end of this train passing through Atlanta, Texas, recently is called a FRED: flashing rear-end device. It vacates the need for a caboose. From the rear of the train, the FRED constantly sends signals to the engineer about the status of the train such as brakes and pressure, load balance and so on. The FRED constantly communicates by GPS to tell the dispatcher where the end of the train is at all times. The light also shines to protect the train’s rear. For these and other reasons, FRED replaced the 10,000-pound caboose, and the employees who once manned the caboose.