Ferrets with jobs: the ferrets who pulled cables through pipes

Who was Felicia the ferret?

Felicia was a small female ferret who worked at the National Accelerator Laboratory (NAL) in Illinois while it was being built. The lab, now known as Fermilab, sits on what a later Fermilab article describes as a 10-square-mile site on the prairie, 40 miles from Chicago. The lab's staff newsletter, The Village Crier, introduced her on 2 September 1971 under the headline "Tiny ferret aids construction of NAL Meson Lab".

The newsletter clearly loved her. "She is not on the NAL payroll nor on Social Security," it said, "but her activities are saving scores of manhours and getting a difficult job done quickly."

What problem did Felicia solve?

Dirty pipes. As the Meson Laboratory was built, the long vacuum pipes that would carry the beam had to be spotless, and The Village Crier says there was a need to swab out stray steel particles left inside them. The University of Chicago Magazine describes the tubes as littered with dust and steel specks.

Getting a cleaning cloth through hundreds of feet of narrow, sealed pipe is hard. Someone first has to get a string from one end to the other.

Whose idea was the ferret?

A visiting British engineer's. The Village Crier says Wally Pelczarski, a designer in NAL's Main Ring Section, had been given the job of designing a mechanical "meson-cleaner". In a conversation with Robert Sheldon, whom the newsletter calls "the innovative Briton", Pelczarski accepted Sheldon's suggestion that live, rather than mechanical, ferrets be used. The University of Chicago Magazine says Sheldon was recalling how ferrets were used on English country estates, where they have long been kept to work in burrows.

Pelczarski then asked a supplier in Gaylord, Minnesota, to send the smallest ferret it had. Back came Felicia, about 15 inches (38 cm) long, which the newsletter says was about 15 per cent smaller than a male. She cost $35.

How did Felicia clean the pipes?

She ran through them with a string. The Village Crier explains that a specially made collar around her neck carried a string or lightweight rope, and Felicia pulled it through the pipe. Workmen then tied a swab to the end of the string and pulled it back through, leaving the pipe clean.

1. Clip on the string. A light string or rope was fastened to Felicia's special collar at one end of the pipe.
2. Run for the light. Felicia ran through the dark pipe towards the light at the far end, carrying the string behind her.
3. Tie on the swab. At the far end, the team fastened a cleaning swab to the string.
4. Pull it through. The workmen pulled the swab back through the pipe, clearing out the dust and steel specks.

Her bendy body did the rest. The lab's May 1972 newsletter said her "naturally elastic body" let her stretch through a space only as large as her head as she headed for the light at the end of the tunnel.

How well did she do?

Very well, while the pipes stayed short enough. By early September 1971 she had made three 300-foot (90 m) runs, with nine more planned for the following months, The Village Crier reported. That would make the "about a dozen runs" the University of Chicago Magazine gives for her whole career.

The team was delighted. Don Richied, a Meson Lab technician, told the newsletter: "Felicia has saved me a lot of time and effort. We'll use her over and over again and perhaps other sections in the Laboratory can put her to work for them as time goes by." The newsletter added that she had cost $35 but saved NAL hundreds, perhaps thousands, of dollars, and joked that the lab's animal head count now included buffalo, cattle, sheep, ducks "and a ferret".

Why did Felicia retire?

The pipes got too long for her. The May 1972 Village Crier says she had been in semi-retirement since the autumn of 1971, when construction produced tube lengths far beyond her range of about 300 feet. A mechanical ferret built by the lab's engineers took over cleaning the vacuum chambers in the Main Ring, which came in eight segments of about 2,600 feet (790 m) each. The University of Chicago Magazine names the engineer as Hans Kautzky and says he called his machine a "magnetic ferret", and it gently notes that the job had grown beyond Felicia's capacity "(or willingness)".

By then she was a star. The University of Chicago Magazine says she became a local, national and international sensation, featured in newspapers, Time magazine, and on television and radio.

What happened to Felicia?

She was well loved to the end. The May 1972 Village Crier reported that Felicia died after a short illness on Tuesday 9 May 1972, despite veterinary care. It said she "made many friends both inside and outside the Laboratory", and that two staff members, Charles Crose and Wally Pelczarski, had given her a great deal of personal attention, including looking after her in their own homes.

One later account remembers it a little differently. In a 2016 Fermilab article, the retired staff member Frank Beck recalls Felicia being brought in during "the late 1960s" to help find an obstruction in the accelerator pipe, and later being pensioned off as the laboratory's pet and mascot. The lab's own newsletters from the time date her work to 1971, so we follow those.

Were other ferrets used to lay cables?

Yes, in the UK in 1999. Tech Monitor reported on 29 December 1999 that network engineers preparing for the millennium party at Greenwich, expected to be watched by a TV audience of a billion, could not dig up turf in a Royal park to lay cables. Their answer, it said, was to drill small tunnels underground and send ferrets in nylon harnesses down them, trailing a wire that was then used to pull the cables through. The ferrets were given a food reward at the end.

We could not find a well-sourced report of other named cable ferrets, so we have left out the many retellings that circulate without a clear source.

Working ferrets at a glance

What does Felicia tell us about pet ferrets?

That a ferret's love of tunnels is real and strong. Felicia was chosen, The Village Crier said, because ferrets are observant, curious animals that seek out holes. Your pet ferret has the same urge, and giving it an outlet is one of the kindest things you can do.

The RSPCA advises giving ferrets hiding places such as tunnels and closed hammocks, suitable toys, and room for hide-and-seek and digging, along with daily exercise in a safe play area. It also recommends keeping more than one ferret, and never shouting at or punishing them.

• Lay out a few wide tubes or tunnels at playtime for running and hiding.
• Add a digging box and a closed hammock for snoozing.
• Hide some of their food so they search for it.
• Give them daily time out in a safe, ferret-proofed area.
• Keep at least two ferrets, so they have company.

Our guide to ferret playtime covers how much they need and which games they love, and our pick of the best ferret toys includes plenty of tunnels. For the full picture, start with our ferret care guide, read up on ferret behaviour and body language, or enjoy more ferret facts.