Long Lines Journal was a video newsmagazine produced for, and broadcast to, employees of AT&T Long Lines, the long distance branch of the Bell System. This story, about the repair of an older undersea cable that ran from Florida to St. Thomas, came from "Issue 15" of the series.
The St. Thomas 1 cable suffered a break around 1980 and went out of service. At the time, it wasn't the only cable serving the same route—but it was still imperative to fix quickly, though voice traffic could be temporarily re-routed along St. Thomas 2, which followed the same path (the original laying of St. Thomas 2 is documented in Voices from the Deep, a film from 1969). St. Thomas 1 carried 142 voice circuits at the time.
The CS Long Lines, still AT&T's cable-laying flagship at the time, was dispatched to find and repair the break. While the news story doesn't quite capture it, this particular repair had some tricky elements to execute. For one, the CS Long Lines had some navigational weak spots—it could maneuver very well on the bow, but the stern was hard to control. And it had to make the repair in a paltry 20 feet of water.
The St. Thomas 1 cable was retired 9 years later, in 1989. It had been originally installed in 1964. Today, AT&T maintains its replacement, Americas-1 North, a fiber-optic cable placed into service in 1994, which handles a whopping 2.5Gb/second of data.
Footage Courtesy of AT&T Archives and History Center, Warren, NJ