The gas chamber was about the size of a large washing machine, and Quentin, an auburn-colored basenji mix with pointy ears, was locked inside with seven other dogs.

The morning of Aug. 4, 2003, started like any other at the St. Louis Animal Control pound, which had been killing six to eight dogs every day, the St. Louis Post-Dispatch reported at the time. First, employees tranquilized 1-year-old Quentin and the other dogs awaiting the chamber. They ushered the dogs inside the airtight box and shut the door. Then, for 15 minutes, they pumped in poisonous carbon monoxide.

But when employee Rosemary Ficken opened the door again, she found something startling: Quentin, staring back at her and wagging his tail — surrounded by dead dogs.

She had never seen anything like it in her 15 years of killing unwanted pets at the city pound, she told the Post-Dispatch. He came out of the gas chamber “walking around like he was a little bit drunk,” while she thought about what to do next. She decided she couldn’t shut the door on him again.

“This dog has a will to live,” she told Post-Dispatch, “and there’s got to be someone out there who’s meant to have him.”

That someone was Randy Grim, the animal welfare advocate and founder of Stray Rescue of St. Louis, who with Quentin, the “miracle dog,” would go on to campaign in a nationwide movement against the use of gas chambers to kill animals.

On Sunday, Grim announced in an emotional post on Stray Rescue that Quentin, long known as the “spokesdog” for pets on death row, died after a stroke. Grim remembered Quentin for his role as a catalyst in the no-kill movement, saying, “Quentin has done more for animal welfare than any human ever could.”

“Surviving the gas chamber in 2003, he picked me to be his partner to close down numerous animal death chambers across the country, but his miracles didn’t stop there,” Grim wrote. “My miracle buddy also helped to spearhead the no-kill movement, an animal abuse task force, a shelter to protect the abused and forgotten, all the while keeping his dad, me, feeling loved and sane. He changed the landscape of an entire city, and I pray his legacy continues to be a driving force for a humane nation for all animals.”

Grim first met Quentin after Ficken called him from the St. Louis Animal Control building, asking whether he would be willing to take in the survivor. Quentin’s name was actually “Cain” then, but Grim soon decided to rename him Quentin after San Quentin State Prison in California, once known for its gas-chamber executions.

At first, Grim intended to place him for adoption. But as Quentin’s miraculous survival gained national attention, about 700 people inquired, and choosing a single family became nearly impossible, Grim told the Post-Dispatch in 2003. He decided to keep him. Within days, the California-based group In Defense of Animals asked Grim whether Quentin might become the “poster dog” to help educate people about millions stray dogs who are killed in shelters each year.

And the campaign was off.

Grim and Quentin began flying around the country for events, animal welfare fundraisers and, eventually, to lobby for legislation once lawmakers began rethinking gas chambers. A November 2003 Chicago Tribune article reported that Quentin was, literally, getting first-class treatment on one recent trip to an animal-welfare event in New York.

“It was really a riot. He got to fly first class,” Grim told the paper. “It was so cute; he sat in the seat and looked out the window like a kid. And he had the chicken. We had our own driver in a long, white stretch limo. Even the hotel — they gave him a feather bed and toys, bowls, everything you can think of. And there was a moment there where I started to cry a little, because I thought, my God, he’s gone from the gas chamber and death to a first-class limousine.”

In the 2008 book “Saved: Rescued Animals and the Lives They Transform,” Grim told author Karin Winegar that he and Quentin had since persuaded 50 communities to shut down their gas chambers — including St. Louis, which banned the use of gas chambers the year after Quentin’s survival. The pair also lobbied the Illinois legislature to ban gas chambers statewide in 2009.

Lethal injection is the preferred method to kill animals because injection causes “rapid loss of consciousness” rather than a buildup of distress or fear among animals being gassed, the Humane Society of the United States said in 2013.

St. Louis Mayor Lyda Krewson offered her condolences to Grim on Twitter upon hearing the news of Quentin’s passing.

“I am very sorry Randy,” she wrote. “You and Quentin changed everything in animal welfare in St. Louis and across the country.”

Quentin “retired” from raising awareness for strays in 2013, living out his final years at Randy’s Rescue Ranch. On-site hospice workers cared for him and other aging dogs daily throughout the last year of his life, Grim wrote in his Stray Rescue post, with Quentin spending most of his time in wide open spaces or lounging inside with other canines. He suffered the stroke Oct. 19, and was euthanized Sunday.

Grim said he buried him at the ranch.

“Everybody,” he said in a video Sunday just before Quentin died, “hug your dogs tight tonight.”

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